Kabushiki Kaisha Toshiba

Mikio Izumi

Teruji Tarumi

Hidehiko Kuroda

Tatsuyuki Maekawa

Toshifumi Sato

Naotaka Oda

Toshiaki Ito

Masafumi Yamada

Toshifumi Hayashi

Kei Takakura

Hideyuki Kitazono

Akira Yunoki

Kunihiko Nakayama

Shigeru Odanaka

Makoto Takemura

Hiroshi Sakamoto

Hiroshi Nakamura

Akio Takahashi

Hiroshi Nishikawa

Michio Sato

Masaki Yoda

Hirotaka Sakai

Naoto Kume

Toshiro Sakai

Akio Sumita

Takanari Inatomi

Masafumi Komai

Mitsuhiro Enomoto

Yoshimi Maekawa

Hiroaki Kenjyo

Tetsuo Goto

Yuka Takada

Syunichiro Makino

Yutaka Kondoh

Masahiko Kamiyama

Katuya Kondoh

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 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 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 survey meter for measuring a radioactive contamination caused in an inner surface of a pipe includes a radiation detecting section and a signal processing section. The radiation detecting section includes a rod-shaped light guide unit, a reflecting portion connected to one end surface of the light guide unit, a photoelectric transfer unit, for outputting an electronic signal, connected to another one end surface of the light guide unit, and a scintillator unit provided to a circumference of the light guide unit. The signal processing section includes a pulse height discriminator for outputting a logic signal at a time when a pulse height value of the electronic signal outputted from the photoelectric transfer unit is higher than a threshold value, a counter unit for counting the logic signal, a contamination judging unit for judging whether a radioactive contamination is caused or not, and a display unit for displaying the value counted by the counter unit and a contamination judging result judged by the contamination judging unit.

Survey meter

A safety protection instrumentation system for a nuclear reactor is constructed by using digital logic. The digital logic includes functional units in which output logic patterns corresponding to all input logic patterns are verified in advance and a functional module formed by combining the functional units.

Safety protection instrumentation system and method of operating the system

An apparatus for verifying a custom IC including a test pattern generating unit for generating a test pattern for verifying a function of the custom IC. The test pattern is output to a master IC and a test IC. The apparatus further includes a comparing unit connected to receive operation signals output from the master IC and the test IC for comparing the operation signals to see if the operation signals are agreed with each other and for generating a comparison signal based on a comparison result, a judging unit connected to receive the comparison signal for judging if there is any abnormality in the test IC and for outputting a judged signal based on a judged result, and a computer connected to receive the judged signal for displaying the judged result of the test IC.

Apparatus and method for verifying custom IC

A plant protection instrumentation equipment, comprises, a sensor that detects a process signal indicating a quantity of a state of a plant, a plurality of A/D converters, each of the A/D converters converts the process signal into a digital signal and outputs a value corresponding to the digital signal, a plurality of instrumentation circuits, each of the instrumentation circuits receives the value corresponding to the process signal and performs a logical operation using the value, and a judgment circuit that judges the state of the plant based on outputs of the plurality of instrumentation circuits and outputs an operation signal based on the process signal, wherein each of the instrumentation circuits comprises a logical integrated circuit including a set value comparator that compares the value corresponding to the process signal with a predetermined set value, and outputs a signal when the value corresponding to the process signal exceeds the set value.

Plant protective instrumentation equipment

A verification method is provided for verifying a safety apparatus including a programmable logic device having a plurality of functional elements. The verification method includes the steps of exhaustively verifying the plurality of functional elements on actual hardware, generating a functional element that is the same as one of the functional elements verified on the actual apparatus using a predetermined hardware description language, independently logic-synthesizing each generated functional element into a plurality of first net lists, generating a connection function between the functional elements using the predetermined hardware description language, logic-synthesizing the generated connection function into a second net list corresponding to the connection function, synthesizing the first net lists with the second net list to generate a third net list, writing a logic circuit into the programmable logic device on the basis of the third net list, and verifying the actual programmable logic device.

Method for verifying safety apparatus and safety apparatus verified by the same

A radiation measurement device includes a radiation detector generating an analog signal containing pulse components, an A/D converter converting the analog signal into sampled data, an n-th power pulse discrimination unit calculating n-th power values of the sampled data to discriminate the pulse component, where n is two or more, and a pulse counter counting a number of the discriminated pulse components.

Radiation measurement device

The reactor start-up monitoring apparatus is provided with an SRNM detector, an analog amplifier, an N/D converter, a pulse measurement system, a Campbell measurement system and reactor power monitoring means. The pulse measurement system is provided with pulse counting means for counting the pulse number of output pulses of the detector from the first digital data from the converter, and pulse measurement evaluating means for converting the measurement value to reactor power and evaluating the reactor power. The Campbell measurement system is provided with sum operating means for adding a plurality of sampling values forming the first digital data from the converter and acquiring the second digital data having accuracy of bits more than those of the first digital data, power operating means for obtaining mean square values based on the second digital data and Campbell measurement evaluating means for converting the mean square values to reactor power and evaluating the reactor power.

Apparatus and method of monitoring reactor power of reactor at the time of startup thereof

Growing community of inventors

Yokohama, Japan

Mikio Izumi