Abstract: Provided is a measurement unit and measurement method for reducing attenuation due to optical fiber length and SN degradation due to background in a dosage rate monitor that uses optical fiber. This system comprises: a radiation detector for detecting radiation dosage; a light source for irradiating stimulating light on the radiation detector; a photodetector for detecting light generated by the radiation detector; an optical fiber for connecting the photodetector and the radiation detector and light source, and transmitting light from the light source and light from the radiation detector; a measurement unit for counting the pulses outputted from the photodetector; and an analysis unit for extracting the luminous energy originating from the radiation detector, from time information, wave height information, and the count value, which are measurement results obtained by the measurement unit, and converting the luminous energy to a dosage and dosage rate.

Abstract: Provided is a measurement unit and measurement method for reducing attenuation due to optical fiber length and SN degradation due to background in a dosage rate monitor that uses optical fiber. This system comprises: a radiation detector for detecting radiation dosage; a light source for irradiating stimulating light on the radiation detector; a photodetector for detecting light generated by the radiation detector; an optical fiber for connecting the photodetector and the radiation detector and light source, and transmitting light from the light source and light from the radiation detector; a measurement unit for counting the pulses outputted from the photodetector; and an analysis unit for extracting the luminous energy originating from the radiation detector, from time information, wave height information, and the count value, which are measurement results obtained by the measurement unit, and converting the luminous energy to a dosage and dosage rate.

Abstract: At a worksite of a client, progeny nuclides of radon and thoron are collected into a filter, then making the gross measurement on ?-ray amount within an hour from the collection. Next, the filter is sent to an analysis center with information added thereto, such as collection-condition information, gross-measurement information, and sampling-worksite information. At the analysis center, the gross measurement on the filter sent thereto is made again. Also, the radioactive-nuclide analysis is made to perform evaluation of the radioactivity intensity. Moreover, radon amount and thoron amount at the measurement-specimen sampling points-in-time at the worksite are calculated, then reporting the analysis result of the radon and thoron amounts to the client.

Abstract: At a worksite of a client, progeny nuclides of radon and thoron are collected into a filter, then making the gross measurement on ?-ray amount within an hour from the collection. Next, the filter is sent to an analysis center with information added thereto, such as collection-condition information, gross-measurement information, and sampling-worksite information. At the analysis center, the gross measurement on the filter sent thereto is made again. Also, the radioactive-nuclide analysis is made to perform accurate evaluation of the radioactivity intensity. Moreover, radon amount and thoron amount at the measurement-specimen sampling points-in-time at the worksite are calculated, then reporting the analysis result of the radon and thoron amounts to the client.

Abstract: An ?-ray measuring apparatus is provided for accurately analyzing the energy of a trace of ?-rays emitted from a sample in a short time using semiconductor detectors which excel in energy resolution. The ?-ray measuring apparatus comprises an ?-ray detector including a plurality of semiconductor detectors, an adder for adding output signals from the respective semiconductor detectors, an anticoincidence counter for anticoincidently counting the output signals from the respective semiconductor detectors, and a peak analyzer for analyzing an energy distribution of the ?-rays based on an addition of the output signals from the semiconductor detectors which are not anticoincidently counted. Since the output signals from the plurality of semiconductor detectors are added to increase the area of a sample under measurement and also remove background noise, the ?-ray measuring apparatus can more accurately analyze the energy of the ?-rays while reducing a measuring time.

Abstract: To provide a radioactive gas measurement apparatus that is simply constructed and can efficiently measure Xe-133 in a radioactive gas on-line under the condition that the radioactive gas is mixed with interference N-13, an apparatus is provided for measuring a radiation emitted from Xe-133, including an anticoincidence counter circuit 13 that conducts counting if it receives an output of a main detector 1 when it does not receive outputs of scintillation detectors 2 and 9, and a gate circuit 14, a plate-shaped semiconductor detector is used as the main detector 1, and a material not emitting a characteristic X ray in the range from 70 to 90 keV is used for a shielding structure. In particular, the thickness of the semiconductor detector 1 is set to fall within a range from 2 mm to 7 mm, thereby improving the analysis precision.

Abstract: To provide a radioactive gas measurement apparatus that is simply constructed and can efficiently measure Xe-133 in a radioactive gas on-line under the condition that the radioactive gas is mixed with interference N-13, an apparatus is provided for measuring a radiation emitted from Xe-133, including an anticoincidence counter circuit 13 that conducts counting if it receives an output of a main detector 1 when it does not receive outputs of scintillation detectors 2 and 9, and a gate circuit 14, a plate-shaped semiconductor detector is used as the main detector 1, and a material not emitting a characteristic X ray in the range from 70 to 90 keV is used for a shielding structure. In particular, the thickness of the semiconductor detector 1 is set to fall within a range from 2 mm to 7 mm, thereby improving the analysis precision.

Abstract: An &agr;-ray measuring apparatus is provided for accurately analyzing the energy of a trace of &agr;-rays emitted from a sample in a short time using semiconductor detectors which excel in energy resolution. The &agr;-ray measuring apparatus comprises an &agr;-ray detector including a plurality of semiconductor detectors, an adder for adding output signals from the respective semiconductor detectors, an anticoincidence counter for anticoincidently counting the output signals from the respective semiconductor detectors, and a peak analyzer for analyzing an energy distribution of the &agr;-rays based on an addition of the output signals from the semiconductor detectors which are not anticoincidently counted. Since the output signals from the plurality of semiconductor detectors are added to increase the area of a sample under measurement and also remove background noise, the &agr;-ray measuring apparatus can more accurately analyze the energy of the &agr;-rays while reducing a measuring time.

Abstract: A highly sensitive charged particle measuring device capable of measuring low-level alpha rays comprises in a measurement chamber 7 provided with a sealable door 15, a test sample 2 and a semiconductor detector 1, a radiation measuring circuit 30 including a preamplifier 30c connected to the semiconductor detector 1, a linear amplifier 30d, and a pulse height analyzer 30e, a charged particle emission amount arithmetic unit 40 for performing the quantitative analysis of charged particles from its measurement, a display unit for displaying its analysis result, and further has an evacuation pipe line and a pure gas supply pipe line for performing supply and replacement of the pure gas in the measuring chamber 7.

Abstract: A highly sensitive charged particle measuring device capable of measuring low-level alpha rays comprises in a measurement chamber 7 provided with a sealable door 15, a test sample 2 and a semiconductor detector 1, a radiation measuring circuit 30 including a preamplifier 30c connected to the semiconductor detector 1, a linear amplifier 30d, and a pulse height analyzer 30e, a charged particle emission amount arithmetic unit 40 for performing the quantitative analysis of charged particles from its measurement, a display unit for displaying its analysis result, and further has an evacuation pipe line and a pure gas supply pipe line for performing supply and replacement of the pure gas in the measuring chamber 7.

Abstract: A highly sensitive charged particle measuring device capable of measuring low-level alpha rays comprises in a measurement chamber 7 provided with a sealable door 15, a test sample 2 and a semiconductor detector 1, a radiation measuring circuit 30 including a preamplifier 30c connected to the semiconductor detector 1, a linear amplifier 30d, and a pulse height analyzer 30e, a charged particle emission amount arithmetic unit 40 for performing the quantitative analysis of charged particles from its measurement, a display unit for displaying its analysis result, and further has an evacuation pipe line and a pure gas supply pipe line for performing supply and replacement of the pure gas in the measuring chamber 7.

Abstract: A highly sensitive charged particle measuring device capable of measuring low-level alpha rays comprises in a measurement chamber 7 provided with a sealable door 15, a test sample 2 and a semiconductor detector 1, a radiation measuring circuit 30 including a preamplifier 30c connected to the semiconductor detector 1, a linear amplifier 30d, and a pulse height analyzer 30e, a charged particle emission amount arithmetic unit 40 for performing the quantitative analysis of charged particles from its measurement, a display unit for displaying its analysis result, and further has an evacuation pipe line and a pure gas supply pipe line for performing supply and replacement of the pure gas in the measuring chamber 7.

Abstract: To provide a radioactive gas measurement apparatus that is simply constructed and can efficiently measure Xe-133 in a radioactive gas on-line under the condition that the radioactive gas is mixed with interference N-13, an apparatus is provided for measuring a radiation emitted from Xe-133, including an anticoincidence counter circuit 13 that conducts counting if it receives an output of a main detector 1 when it does not receive outputs of scintillation detectors 2 and 9, and a gate circuit 14, a plate-shaped semiconductor detector is used as the main detector 1, and a material not emitting a characteristic X ray in the range from 70 to 90 keV is used for a shielding structure. In particular, the thickness of the semiconductor detector 1 is set to fall within a range from 2 mm to 7 mm, thereby improving the analysis precision.

Abstract: A neutron individual dose meter and a neutron dose rate meter, both capable of implementing the effective dose equivalent response. The neutron individual dose meter is capable of being accomplished by providing a composite layer made up of a converter such as boron, and a proton radiator, on the surface of a semiconductor neutron detection element. The neutron dose rate meter is capable of being accomplished through such a structure as to surround a neutron detector with a neutron moderator and a thermal neutron absorber which has openings. Thus, a neutron individual dose meter and a neutron dose rate meter, both capable of implementing the effective dose equivalent response and measurement at lower operating voltage have been provided. Further, these meters are capable of being implemented by utilizing a single semiconductor detection element, respectively.

Abstract: A field control apparatus for a generator having a field winding comprises a terminal voltage control unit for controlling a field current of the generator in accordance with a difference between a terminal voltage signal of the generator and a reference voltage signal, which control unit has at least one of a line drop compensation function, an under-excitation limitation function, an over-excitation limitation function, a power factor regulation function, an armature winding over-current compensation function and a cross-current compensation function. The field control apparatus includes a detector as a common signal source for detecting active power and reactive power components at an output terminal of the generator and means responsive to the output of the detector for performing scalar operation in accordance with a function of the added compensation/control function described above.