JP5761808B2 - Radiation measurement apparatus and data communication system and radiation abnormality determination system - Google Patents

Description

  The present invention relates to a radiation measuring apparatus for measuring a radiation dose emitted from a radioactive substance.

People from all over the world are interested in the effects of radiation on the human body due to the accident that occurred at the Fukushima Daiichi nuclear power plant in Japan, especially those who live in areas where radioactive materials are thought to have been scattered Since then, there have been many requests for measuring the radiation dose in the region by hand.
Conventionally, a simple type radiation measuring apparatus capable of meeting such demands has been proposed (see, for example, Patent Documents 1 and 2), but it is difficult to say that both have sufficient measurement accuracy.

JP-A-7-306268 JP 2005-321274 A

The present invention has been developed to meet the above-mentioned needs of the people, and an object thereof is to provide a radiation measuring apparatus capable of obtaining radiation energy with high accuracy with a simple structure.
It is another object of the present invention to provide a data communication system that can determine that data measured and transmitted by a radiation measurement apparatus has not been tampered with and obtain a highly accurate analysis result.
Another object of the present invention is to provide a communication system for data output from the radiation measurement apparatus and a radiation abnormality determination system capable of accurately determining a radiation abnormality based on the data output from the radiation measurement apparatus.

In order to achieve the above object, the present invention comprises a detector that detects the energy of radiation and outputs an analog electrical signal having a wave height corresponding to the energy.
An integrating amplifier that amplifies and outputs the analog electrical signal output from the detector;
An A / D converter for digitally converting the output signal from the integrating amplifier at a preset sampling interval;
A data processing unit that processes the digitally converted electrical signal and obtains the energy of the radiation input to the detector;
The integrating amplifier is characterized in that a time constant is set so that the output signal is discharged over a longer time than the sampling interval of the A / D converter.

  With this configuration, when sampling in the A / D converter, it is possible to avoid an error that misses the output signal from the integrating amplifier and to perform highly accurate data processing.

Here, it is preferable to set the time constant of the integrating amplifier to a value that can suppress the decrease in the peak value of the output signal within 5% in the sampling interval of the A / D converter.
By setting in this way, the peak value of the output signal from the integrating amplifier or the peak value in the vicinity thereof can be reliably sampled by the A / D converter. The peak value of the output signal from the integrating amplifier is a value corresponding to the energy of the radiation detected by the detector. By enabling sampling of such peak peak value or at least the peak value in the vicinity thereof, high-precision radiation Energy can be obtained.

  Further, by using a compound semiconductor detector as the detector, it can be manufactured at a lower cost than a scintillation detector having a similar function.

The present invention comprises a second detector configured with a Geiger-Muller detector;
A comparator that outputs a pulsed signal when the analog electrical signal output from the second detector exceeds a preset threshold;
A counter for counting the number of signal outputs from the comparator,
A configuration in which the data processing unit obtains the number of detected radiation per unit time (cpm) based on the output from the counter may be added.

  In addition, the number of detected radiation per unit time (based on the output from the second detector) by the data processing unit determined by the conversion coefficient specified by the energy of the radiation determined based on the output from the detector ( If a configuration having a function of converting cpm) into a dose equivalence rate (μSv / h or the like) representing the degree of influence on the human body by radiation, such data conversion can be performed with high accuracy. In the present specification, units such as cpm and μSv / h are indicated, but the present invention is not limited to these units.

When converting the radiation detection number data (cpm) per unit time obtained based on the output from the Geiger-Muller detector into a dose equivalent rate (μSv / h, etc.) representing the degree of influence of radiation on the human body, The conversion process is executed with a predetermined arithmetic expression using the conversion coefficient. Here, since the known conversion factor varies greatly depending on the nuclide (radioactive substance) emitting radiation and the energy of the radiation, unless the nuclide or energy is specified, the dose equivalent rate (μSv / h, etc.) is determined. ) Cannot be accurately converted.
In a conventional radiation measurement apparatus using a Geiger-Muller detector that is commercially available, the most likely nuclide (for example, cesium 137) is considered to be the most common without performing nuclide identification or radiation energy measurement. As a result, a conversion factor is specified, and a method of converting from cpm to a dose equivalent rate (μSv / h, etc.) has been adopted. Therefore, the measurement result of the dose equivalent rate (μSv / h, etc.) in this type of simple radiation measurement apparatus is not reliable.

On the other hand, in the present invention, since the conversion coefficient is specified by the radiation energy obtained based on the output from the detector, the dose equivalence rate (μSv / h, etc.) representing the degree of influence of radiation on the human body is highly reliable. It can be determined with sex.
Note that the present invention also includes a configuration in which a nuclide is identified from the radiation energy obtained based on the output from the detector and a conversion coefficient is obtained from the nuclide.

Specifically, it has a memory that stores a radioisotope database in which the peak position and intensity of radiation energy are registered for each nuclide,
The data processing unit obtains a spectrum of radiation based on an output from the detector, performs a smoothing process on the spectrum, then performs a background removal process to extract a peak component, and a peak position from the extracted peak component The nuclide identification process is performed by comparing the peak position and intensity with the radioisotope database, the conversion coefficient is identified from the identified nuclide, and the conversion coefficient is determined from the second detector. A function is provided for converting the number of detected radiation per unit time determined based on the output of the above into data of a dose equivalent rate representing the degree of influence of radiation on the human body.

In addition, it has a memory that stores in advance a radioisotope database in which the spectrum of radiation is registered for each nuclide,
The data processing unit obtains a spectrum of radiation based on an output from the detector, performs a smoothing process on the spectrum, and then performs a nuclide identification process by comparing the entire spectrum with the radioisotope database. Dose equivalence rate representing the degree of influence of radiation on the human body by identifying the conversion coefficient from the nuclide and using the conversion coefficient to determine the number of detected radiation per unit time based on the output from the second detector. It can also be set as the structure provided with the function converted into this data.

In addition, the radiation measuring apparatus according to the present invention can construct a data communication system that sends data output from the data processing unit to an external server.
That is, the radiation measuring device
A unique hash value (apparatus hash value) for each piece of data output from the data processing unit based on parameters including an encryption key set in advance for each individual radiation measurement device and data output from the data processing unit Device hash value generation means for generating
Data transmission means for transmitting data including data output from the data processing unit and the device hash value, and
The encryption key is not transmitted to the outside from the data transmission means,
The server stores a hash value in the same manner as the radiation measurement device based on the means for storing the encryption key set in each radiation measurement device to which data is sent in advance and the data sent from the encryption key and the radiation measurement device. Means for generating (comparison device hash value) and presence / absence of falsification of data sent from the radiation measurement device by comparing the generated comparison device hash value with the device hash value sent from the radiation measurement device And a means for discriminating between them can be constructed.

Furthermore, the mobile terminal that receives the data sent from the radiation measurement device and transmits it to the server via the Internet,
Mobile devices
Receiving means for receiving data sent from the radiation measuring device;
A terminal hash that generates a hash value (terminal hash value) unique to the mobile terminal based on a parameter including the device hash value included in the data sent from the radiation measurement apparatus and data added by the mobile terminal Value generation means;
Terminal data transmission means for collectively transmitting data sent from the radiation measurement device, terminal hash value, and data added by the portable terminal to the server,
The server generates a hash value (comparison terminal hash value) based on data received from the mobile terminal, and a terminal hash value sent from the mobile terminal to the generated comparison terminal hash value. And a means for discriminating whether or not the data sent from the portable terminal has been tampered with.

In addition, the radiation measuring apparatus according to the present invention can also construct a radiation abnormality determination system that determines a radiation abnormality based on data transmitted from a large number of users having the apparatus.
That is, the radiation measuring apparatus adds time data to the data output from the data processing unit and transmits the data to the portable terminal possessed by the user together with the means for outputting the data related to the measurement time (time data). Data transmission means for
The portable terminal has a function of acquiring position information using GPS, and functions as a relay base that adds the position information to data sent from the radiation measuring apparatus and transmits the data to an external server via the Internet. With
The external server can construct a system having a function of discriminating radiation abnormality based on data including position information transmitted from the mobile terminal.

Here, the server can be configured to discriminate radiation abnormality based on the following criteria.
(A) The data output from the data processing unit of the radiation measuring apparatus possessed by many users indicates an abnormality of the radiation, and the amount of change of the radiation with the passage of time is smaller than a predetermined threshold value and When the radiation measuring apparatus to which data indicating radiation abnormality is concentrated in an area narrower than the predetermined range, it is determined that a hot spot exists in the area (b) Radiation measurement possessed by many users The data output from the data processing unit of the apparatus indicates an abnormality in radiation, the amount of change in radiation over time is smaller than a predetermined threshold value, and data indicating the abnormality in radiation has been sent. When the radiation measuring apparatus is dispersed in an area wider than the predetermined range, it is determined that wide-area contamination has occurred in the area.

According to the radiation measuring apparatus of the present invention, the energy of radiation can be obtained with high accuracy with a simple structure.
Further, it is possible to determine that the data measured and transmitted by the radiation measuring apparatus has not been tampered with, and to obtain a highly accurate analysis result.
Furthermore, according to the radiation abnormality determination system of the present invention, it is possible to accurately determine a radiation abnormality based on data output from the radiation measuring apparatus.

It is a figure which shows the external appearance of the radiation measuring device which concerns on embodiment of this invention, (a) is a front view, (b) is a right view, (c) is a rear view. It is a figure which shows the protective cover with which the radiation incident surface of a GM detector is mounted | worn, (a) is the perspective view which looked at the front side, (b) is the perspective view which looked at the back side. It is a block diagram which shows the outline | summary of the signal processing system in the radiation measuring device which concerns on embodiment of this invention. FIG. 4 is a block diagram showing an outline of a signal processing system following FIG. 3. (A) is a diagram showing a configuration example of an integration amplifier, (b) is a diagram showing an example of an analog electric signal input to the integration amplifier, and (c) and (d) are examples of output signals from the integration amplifier, respectively. FIG. (A) is a figure for demonstrating the relationship between the time constant of an integral amplifier, and the sampling interval of an A / D converter, (b) is a figure which shows the example of the radiation spectrum calculated | required in the central processing part. It is a flowchart which shows the data conversion process in nuclide identification and data conversion mode. It is a table | surface which shows an example of the database used for identification of a nuclide. It is a table | surface which shows the specific example which performed the identification process with respect to the spectrum of FIG.6 (b). It is a figure for demonstrating the data communication system using the radiation measuring device of this embodiment which concerns on embodiment of this invention. It is a figure for demonstrating the function to discriminate | determine the presence or absence of the tampering of the transmission data integrated in the data communication system. FIG. 12 is a diagram for describing a function for determining whether transmission data included in the data communication system is falsified, following FIG. 11. FIG. 13 is a diagram for describing a function for determining whether transmission data included in the data communication system is falsified, following FIG. 12. FIG. 14 is a diagram for describing a function for determining whether transmission data included in the data communication system is falsified, following FIG. 13. It is a flowchart for demonstrating the radiation abnormality determination function with which an external server is provided. It is a figure for demonstrating a mesh division | segmentation analysis.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Structure of radiation measurement equipment]
FIG. 1 is a view showing the appearance of the radiation measuring apparatus according to the present embodiment, and FIG. 2 is a view showing a protective cover attached to the radiation incident surface of the GM detector.

First, the external configuration of the radiation measuring apparatus according to the present embodiment will be described with reference to FIG.
As shown in FIG. 1A, the radiation measuring apparatus has an operation unit 2 and a display unit 3 arranged on the front of the apparatus body 1, and the apparatus is operated by pressing various operation buttons provided on the operation unit 2. Can be activated or deactivated. The display unit 3 is composed of, for example, a liquid crystal panel, and detection results and guidance necessary for each operation are displayed on the display unit 3.

  Further, as shown in FIG. 1C, a radiation incident surface 10a of a Geiger-Muller detector (hereinafter referred to as GM detector) 10 (second detector) is disposed on the back surface of the apparatus main body 1. . As is well known, the GM detector 10 is a radiation detector that can capture α rays, β rays, and γ rays and detect these radiation doses, and is widely used in commercially available radiation measuring apparatuses. . The GM detector 10 outputs a pulsed electric signal corresponding to the amount of incident radiation, but has no radiation energy resolution. Therefore, the energy of radiation cannot be obtained.

Here, in the GM detector 10, a thin film made of mica that transmits not only γ rays but also α rays and β rays is used as a window material, and a radiation incident surface 10a is formed. Since the working gas decompressed to about 1/10 atm is enclosed inside the GM detector 10, there is a risk of damage when touching the window material. Therefore, a mesh-like reinforcing portion 10b is provided on the radiation incident surface 10a with a metal material as shown in FIG. Furthermore, on the radiation incident surface 10a of the GM detector 10,
A protective cover 4 having a cap shape as shown in FIG. 2 is detachable. The protective cover 4 is formed of a plastic material or a metal material that shields α rays and β rays and transmits γ rays. In a state where the protective cover 4 is attached to the radiation incident surface 10a of the GM detector 10, the GM detector 10 detects only γ rays. On the other hand, in a state in which the protective cover 4 is removed from the radiation incident surface 10a of the GM detector 10, α rays, β rays, and γ rays are captured. Therefore, the radiation doses of α rays and β rays can be obtained from the difference between the detection data with the protective cover 4 removed and the detection data with the protective cover 4 attached.

  Although not shown in the figure, the apparatus main body 1 incorporates a sensor for detecting whether or not the protective cover 4 is attached to the radiation incident surface 10a, and detects various types of radiation depending on the presence or absence of the protective cover 4. The internal circuit settings can be automatically changed to the optimum specifications.

Further, the compound semiconductor detector 20 is built in the apparatus main body 1 with the radiation incident part facing the back side of the apparatus main body 1.
As is well known, the compound semiconductor detector has an energy resolution superior to that of other radiation detectors, and therefore has a feature that the energy of radiation can be accurately measured. Known semiconductors include single-element semiconductors such as silicon and germanium, and compound semiconductors such as CdTe (Cadmium Telluride, cadmium telluride) and InSb (Indium Antimonide). In this embodiment, radiation absorption efficiency is known. And a CdTe (Cadmium Telluride) system that can increase the resistance at room temperature because of its high band gap. The CdTe-based compound semiconductor detector 20 is a highly sensitive detector that operates at room temperature without using a photoelectric effect to convert radiation into light unlike the scintillation detector. The CdTe-based compound semiconductor detector 20 functions as a detector that detects the energy of radiation and outputs an analog electrical signal having a wave height corresponding to the energy. The compound semiconductor detector 20 is mainly suitable for detecting γ rays. The apparatus main body 1 is made of plastic, and γ rays pass through the apparatus main body 1 and enter the radiation incident portion of the compound semiconductor detector 20.

  As shown in FIG. 1, a connector 6 for connecting an external detector is provided on the upper surface of the apparatus body 1, and either the scintillation detector 30 or the 3He neutron detector 40 is optionally connected via this connector 6. Connection is possible. The connector 6 has multiple pins, and can input and output a high-voltage power supply, a detector signal, a temperature sensor signal, and a detector connection signal.

  As shown in FIG. 1B, a socket for an external connection interface 73 such as a USB is provided on the side surface of the apparatus main body 1. The base portion of the apparatus main body 1 forms a grip portion 5 that can be gripped by an operator with one hand.

[Signal processing system of radiation measurement equipment]
3 and 4 are block diagrams showing an outline of a signal processing system in the radiation measuring apparatus according to the present embodiment.
Next, the configuration of the signal processing system of the radiation measuring apparatus according to the present embodiment will be described with reference mainly to FIGS. 3 and 4. All the constituent elements included in the signal processing system shown in these figures are built in the apparatus main body 1.

As shown in FIG. 3, the radiation measuring apparatus according to the present embodiment can be connected to the scintillation detector 30 and the 3He neutron detector 40 as an option in addition to the GM detector 10 and the compound semiconductor detector 20 described above. ing. These detectors can optionally be omitted.
As the scintillation detector 30, for example, a NaI (Tl) scintillation detector is suitable. The NaI (Tl) scintillation detector uses sodium iodide (NaI) crystals (including thallium) as a detector, and amplifies the fluorescence generated when radiation enters the crystals to convert them into electrical signals. It is the composition to do. This scintillation detector 30 is mainly suitable for detecting γ-rays like the compound semiconductor detector 20, and functions as a detector that detects the energy of radiation and outputs an analog electric signal having a wave height corresponding to the energy. To do.
The 3He neutron detector 40 is a proportional counter using helium 3 (3He), and is configured to detect electric charges generated when 3He absorbs neutrons and thereby convert the electric signals into electric signals.

Each of these detectors is operated by being supplied with power from a high voltage power supply circuit (HV circuit) 50. The high voltage power supply circuit 50 uses a CWC (Cockcroft-Walton's high-voltage circuit) 51. The CWC 51 is a circuit in which a combination of a rectifier and a capacitor is stacked in multiple stages, and can generate a stable DC high voltage from an AC voltage.
Among the detectors described above, the GM detector 10 requires a power supply of, for example, about 950V, while the compound semiconductor detector 20, the scintillation detector 30 and the 3He neutron detector 40 have, for example, a power supply of about 700V. Power supply is required. The high voltage power supply circuit 50 composed of the CWC 51 can supply power of these different voltages. Therefore, it is not necessary to provide a power source for each detector, and the apparatus main body 1 can be miniaturized.

  In the present embodiment, as described later, since only one system of the A / D converter 25 is provided, detection of any one of the compound semiconductor detector 20, the scintillation detector 30, and the 3He neutron detector 40 is performed. The selector 23 is switched based on an operation command from the operation unit 2 and output to the A / D converter 25. Further, the signals of these detectors can be output to the counter 42 without being output to the A / D converter 25. The high voltage power supply circuit 50 has a sufficient capacity and can supply a stable high voltage to all connected detectors.

When radiation enters the GM detector 10, the internal gas is ionized and amplified to output a pulsed analog electrical signal. Since the analog electrical signal from the GM detector 10 includes a noise component, the noise component is removed by the comparator 11 in which a certain threshold is set, and a pulse corresponding to the radiation dose incident on the GM detector 10. Only an analog electric signal in the form of a line is taken out.
The pulse-like analog electric signal is counted by the counter 12, and the counted data is sent to a central processing unit (CPU) 61 shown in FIG. The central processing unit 61 executes a data processing program stored in advance in the memory 62, obtains the number of detected radiation per unit time (radiation count rate: cpm) from the count data from the counter 12, and detects this. As a result, it is displayed on the display unit 3. Here, the central processing unit 61 functions as a data processing unit that obtains the number of detected radiation per unit time based on the output from the counter 12.

  In addition, in the data processing program, a conversion coefficient is specified assuming a nuclide (eg, cesium 137) that is normally considered to be the most common, as in a conventional radiation measurement apparatus, and the number of radiation detections per unit time (radiation) A mode for converting from a counting rate (cpm) to a dose equivalent rate (μSv / h, etc.) is included, and when this mode is selected in the operation unit 2, doses etc. that are simply converted by such conversion factors The amount rate (μSv / h, etc.) is displayed on the display unit 3.

Next, when radiation enters the compound semiconductor detector 20, an analog electrical signal having a wave height corresponding to the energy of the radiation is output. The analog electric signal output from the compound semiconductor detector 20 is amplified by an integrating amplifier (PreAMP) 21 and output.
As shown in FIG. 5A, the integrating amplifier 21 uses an operational amplifier, and the charge of the input analog electric signal is stored in the capacitor C and then gradually discharged through the resistor R. It will be done.

5B shows an example of an analog electric signal input to the integrating amplifier 21, and FIGS. 5C and 5D show examples of output signals from the integrating amplifier 21. FIG. From the compound semiconductor detector 20, an analog electric signal as shown in FIG. 5B having a peak value corresponding to the energy of the incident radiation is output, and this signal is input to the integrating amplifier 21.
The integrating amplifier 21 outputs a triangular wave electrical signal in which the peak value gradually decreases from the peak peak values L1 and L2 corresponding to the radiation energy (FIG. 5C).
When radiation enters the compound semiconductor detector 20 in succession, analog electric signals are output from the detector 20 at short intervals. In this case, as shown in FIG. 5D, the output signal from the integrating amplifier 21 is output next to, for example, a triangular wave-like electric signal whose peak value gradually decreases from the peak peak value L1. A triangular wave electrical signal having a peak peak value L2 is output in the state of a sawtooth wave in which the signals are overlapped. The peak value L2 of the overlapped electrical signal can be obtained starting from the intersecting point.

  The output signal from the integrating amplifier 21 is further amplified by the second amplifier 22, the gain is adjusted by the variable gain amplifier 24 through the selector 23, and sent to the A / D converter 25. Since the output from the compound semiconductor detector 20 has low sensitivity, the second amplifier 22 is provided to further amplify and output the output of the integrating amplifier 21. The variable gain amplifier 24 is provided to perform sensitivity adjustment (calibration) of the compound semiconductor detector 20 and a scintillation detector 30 described later.

  The A / D converter 25 digitally converts the input analog electrical signal at a preset sampling interval. The sampling interval of the A / D converter 25 is preferably 1 μsec or less. By setting the sampling interval to such a short time, it is possible to input an analog electric signal at an interval equal to or smaller than the dead time of the compound semiconductor detector 20, and highly accurate signal conversion without leakage. Is possible.

The time constant of the integrating amplifier 21 is set to a value that discharges the output signal a over a time longer than the sampling interval D of the A / D converter 25 as shown in FIG. In the present embodiment, the time constant of the integrating amplifier 21 is set to a value at which the decrease in the peak value of the output signal can be suppressed within 5% (preferably within 2%) at the sampling interval D of the A / D converter 25. is there.
By setting in this way, the peak peak value of the output signal from the integrating amplifier 21 or the peak value in the vicinity thereof can be reliably sampled by the A / D converter 25. The peak peak value of the output signal from the integrating amplifier 21 is a value corresponding to the energy of the radiation detected by the compound semiconductor detector 20, and the peak peak value or at least a peak value in the vicinity thereof can be sampled. Highly accurate radiation energy can be obtained.

The signal digitally converted by the A / D converter 25 is sent to the central processing unit 61.
The central processing unit 61 executes a data processing program stored in the memory 62 in advance, performs waveform processing on the input signal, and decomposes energy for each peak value of the signal, as shown in FIG. 6B. A simple radiation spectrum.
Here, when the central processing unit 61 performs waveform processing on the signal input from the A / D converter 25, if the signals to be processed overlap as shown in FIG. The coordinate position of the lower end of the signal rise) is obtained, and the peak wave height value L2 is calculated from the height from the coordinate position to the peak position.

In the present embodiment, the gain of the variable gain amplifier 24 is adjusted so that the peak value with respect to radiation with energy 1 MeV is about 1V. The A / D converter 25 can input a sufficiently high peak value (for example, 5 V), and even if a high count rate of radiation is incident with insufficient attenuation of the triangular wave, the A / D is not saturated. It can be converted.
Furthermore, in order to obtain an accurate energy value, calibration work is performed in advance to obtain the relationship between energy and wave height. That is, radiation generated from a standard radiation source including a plurality of known radioisotopes is measured, gain and baseline calibration coefficients are obtained from the relationship between energy and wave height, and recorded in the memory 62. Using this calibration coefficient, the measured peak value is converted into an accurate energy value.

  For example, in this embodiment, the radiation energy 2 MeV (million electron volts) is equally divided into about 1024 regions every about 2 keV (kiloelectron volts), and the detected individual radiation energy is assigned to each divided area. The number classified into each area is counted. A spectrum as shown in FIG. 6b can be obtained by creating a histogram with the horizontal axis representing energy and the vertical axis representing the number. Here, the maximum value on the horizontal axis corresponds to 2 MeV. In addition, the maximum value of radiation energy and the number of divisions can be set arbitrarily.

  Furthermore, the central processing unit 61 performs conversion from the radiation spectrum to the dose equivalent rate (μSv / h, etc.) and identification of the radionuclide according to the detection mode selected by the operation unit 2, and the data The processing result is displayed on the display unit 3 as a detection result.

  In the present embodiment, the number of radiation detections per unit time determined from the output from the GM detector 10 by identifying the radionuclide based on the data acquired by the compound semiconductor detector 20 and using the nuclide. A nuclide identification / data conversion mode is set in which the central processing unit 61 converts (radiation count rate: cpm) to a dose equivalent rate (μSv / h, etc.) that represents the degree of influence of radiation on the human body with high accuracy. .

[Nuclide identification and data conversion processing by radiation measurement equipment]
Next, the data conversion process in the nuclide identification / data conversion mode will be described mainly with reference to FIG.
In the present embodiment, a program for performing radionuclide identification using a spectrum obtained from detection data of the compound semiconductor detector 20 is stored in the memory 62 in advance. The central processing unit 61 executes data conversion processing in the nuclide identification / data conversion mode according to this program.
That is, the central processing unit 61 obtains a spectrum from the detection data of the compound semiconductor detector 20 (step S1), and then performs a smoothing process (smoothing process) on the spectrum by a known means such as “moving average method”. Then, the noise component is reduced (step S2). Next, background removal processing is performed by a known means (step S3), and only the peak component of the spectrum is extracted. Since this peak component relates to the spectrum, the width direction (corresponding to the horizontal axis in FIG. 6B) is energy, and the height direction (corresponding to the vertical axis in FIG. 6B) is the count value. .
In the present embodiment, a plurality of detectors are used, and the shape of the background is different for each detector. Therefore, a means called the Sonnerveld-Visser method that can calculate the background regardless of the shape is adopted. .

  The extracted peak component is collated with the radioisotope database, and nuclide identification processing is performed (step S4). Then, the central processing unit 61 specifies the conversion coefficient from the identified nuclide, and calculates the number of radiation detections per unit time (radiation count rate: cpm) obtained from the output from the GM detector 10 to the human body by radiation. The dose is converted into a dose equivalent rate (μSv / h, etc.) representing the degree of influence (step S5), and the conversion result is displayed on the display unit 3.

  Here, as the nuclide identification algorithm performed in step S4, for example, one of the following two means can be employed.

1) Means for calculating peak position and intensity and pattern matching with database Differentiating the spectrum of the peak component extracted above with energy. The differential value is “positive” at the rising edge of the peak and “negative” at the falling edge. A point crossing “0” indicates a peak position (peak energy), and the intensity at that position is the peak intensity. In the case of a spectrum having a plurality of peaks, a table of peak positions and peak intensities is created.
A database of the format shown in FIG. 8 is created and stored in the memory 62 in advance. Then, the obtained peak table is collated with the database, and the abundance ratio of the nuclides is calculated by the least square method.

2) Means for matching the entire spectrum with the database In the above means 1), for example, when cesium 134 and cesium 137 are detected by a NaI scintillation counter, it is difficult to separate and separate multiple peaks within the energy resolution range. . In order to solve this, instead of the method 1), a method of pattern matching for the entire spectrum is preferable. When nuclide identification is performed by this method, the entire spectrum including the peak component and the background component is targeted, and therefore the background removal process in step S3 can be omitted. In this method, the relationship between the measured spectrum and the nuclide content is expressed by the following equation (1).

ここで、「ｙ」は測定データを示すベクトル（１０２４要素の強度）、「Φ」はデータベースにより構成される行列（１０２４行×６４列）、「θ」はそれぞれの核種の含有量を表すベクトル（６４要素の含有量）、「ｅ」は誤差を表すベクトル（１０２４要素）である。

Here, “y” is a vector indicating measurement data (intensity of 1024 elements), “Φ” is a matrix (1024 rows × 64 columns) constituted by a database, and “θ” is a vector indicating the content of each nuclide. (Content of 64 elements), “e” is a vector (1024 elements) representing an error.

次に、上記の式（２）に従い、最小二乗法により、θを最適化することにより核種含有量を求めることができる。
ここで、あらかじめ線形最小自乗法の正規方程式（一般化逆行列）を計算しておくことにより、計算時間を短縮することができる。すなわち、６４行×１０２４列の行列である（Φ^TΦ）^-1Φ^Tをあらかじめ計算して、メモリ６２に保存しておけば、単純な計算のみで核種同定を行うことが可能である。
この方法では、データベースをピーク成分とバックグラウンドを含むスペクトルの形で保管しているため、検出効率のエネルギ依存性やコンプトン散乱、エスケープピークなどもデータベースに含ませることができ、同定の精度を向上することができる。この場合、測定スペクトルからバックグラウンドを除去する処理は不要になる。さらに、式（２）の一般化逆行列に単位変換成分を含ませておくことで、計算結果を線量等量率（μＳｖ／ｈなど）とすることも可能になる。

Next, according to the above equation (2), the nuclide content can be obtained by optimizing θ by the method of least squares.
Here, the calculation time can be shortened by calculating a normal equation (generalized inverse matrix) of the linear least square method in advance. That is, if (Φ ^T Φ) ⁻¹ Φ ^T which is a matrix of 64 rows × 1024 columns is calculated in advance and stored in the memory 62, nuclide identification can be performed by simple calculation.
In this method, since the database is stored in the form of a spectrum including peak components and background, the energy dependency of detection efficiency, Compton scattering, escape peak, etc. can be included in the database, improving the accuracy of identification. can do. In this case, the process of removing the background from the measurement spectrum is not necessary. Furthermore, by including a unit conversion component in the generalized inverse matrix of Equation (2), the calculation result can be a dose equivalent rate (μSv / h, etc.).

  FIG. 9 shows a specific example in which the identification process is performed on the spectrum of FIG. Here, for the test, the identification process was performed by excluding the cesium 136 component from the database. As a result, a peak that cannot be identified appears at 1048 keV, and the other peaks are identified, indicating the correctness of the algorithm.

In this embodiment, the energy is divided into 1024. However, since the energy resolution of the semiconductor detector is about 1% and the energy resolution of the scintillation detector is about several percent, the number of divisions when performing the identification processing is 256, 128. , It can be reduced to about 64.
Moreover, although the nuclide is 64 types, it may be about 30 types in practical use.
Furthermore, it is preferable that the user can add the nuclide actually measured in each environment to the database, and a configuration having a function capable of recalculating the generalized inverse matrix can also be adopted.

When the scintillation detector 30 is selected in the operation unit 2, the switch 32 connects the integration amplifier 31 (PreAMP) to the selector 23, and the selector 23 sends the analog electric signal from the integration amplifier 31 to the variable gain amplifier 24. The circuit configuration is changed.
When radiation enters the scintillation detector 30, an analog electrical signal having a wave height corresponding to the energy of the radiation is output. The analog electric signal output from the scintillation detector 30 is amplified by the integrating amplifier 31. The integrating amplifier 31 has a function similar to that of the integrating amplifier 21 shown in FIG. The analog electric signal amplified by the integrating amplifier 31 is adjusted in gain by the variable gain amplifier 24 via the selector 23 and sent to the A / D converter 25. The A / D converter 25 converts the input analog electric signal into a digital signal and sends it to the central processing unit 61. The central processing unit 61 executes a data processing program stored in the memory 62 in advance, performs waveform processing on the input digital signal, and performs data processing similar to the data from the compound semiconductor detector 20.

Next, when the 3He neutron detector 40 is selected in the operation unit 2, the switch 32 connects the integrating amplifier 31 and the comparator 41.
When a neutron beam enters the 3He neutron detector 40, an analog electric signal corresponding to the neutron dose is output. Since the analog electrical signal from the 3He neutron detector 40 includes a noise component, the noise component is removed by the comparator 41 having a certain threshold value, and corresponds to the neutron dose incident on the 3He neutron detector 40. Only the analog electrical signal is extracted.
The analog electric signal is counted by the counter 42 and the counted data is sent to the central processing unit 61. The central processing unit 61 executes a data processing program stored in advance in the memory 62 and obtains a neutron dose from the count data from the counter 42.

  In the present embodiment, as shown in FIG. 4, a microcomputer (one chip) in which all the components including the counters 12 and 42, the A / D converter 25, the central processing unit 61, and the memory 62 are made of one chip. The microcomputer 60 is comprised. Therefore, it is possible to reduce the size of the apparatus main body 1 with less hardware.

[Outline of data communication system]
FIG. 10 is a diagram for explaining a data communication system using the radiation measuring apparatus according to the present embodiment according to the present embodiment.
The radiation measuring apparatus 100 according to the present embodiment includes a communication module 72 as shown in FIG. 4, and transmits data related to radiation processed by the central processing unit 61 to the mobile terminal 101 via the communication module 72. It has a function to do.

  As the communication module 72, various wireless communication means that can perform data communication with the mobile terminal 101, such as Bluetooth (registered trademark), wireless LAN, and infrared communication, can be applied. Data can also be sent to the mobile terminal 101 not via the communication module 72 but via the external connection interface 73 such as USB. The communication module 72 and the external connection interface 73 function as data transmission means for sending data related to radiation output from the central processing unit 61 (data processing unit) of the radiation measuring apparatus 100 to the portable terminal 101.

  Examples of the portable terminal 101 include a mobile phone, a smartphone, a PDA (Personal Digital Assistants), a UMPC (Ultra Mobile Personal Computer), a netbook, a notebook personal computer, a car navigation system, and the like. If necessary, a stationary personal computer or the like can be applied instead of the portable terminal 101.

The data to be sent to the portable terminal 101 includes the measurement start time (in this embodiment, the time when the central processing unit 61 starts inputting the signal) and the count number, and may further include the nuclide identification result or spectrum. The measurement start time data is output from a timer 71 built in the apparatus body 1 (see FIG. 4).
Data sent to the mobile terminal 101 is stored in the memory of the mobile terminal 101.
Data on radiation stored in the memory can be displayed on the display screen of the mobile terminal 101. For example, data such as a radiation spectrum is easier to visually recognize when displayed on the display screen of the high-definition portable terminal 101.

  Further, the mobile terminal 101 has a position information acquisition function using a GPS (Global Positioning System) 102. By providing the portable terminal 101 with such a function, it is possible to add position information to the radiation-related data acquired by the radiation measuring apparatus 100 of the present embodiment and save it in the memory. Since the radiation measuring apparatus 100 and the portable terminal 101 are usually carried by the user and act together, the position information is acquired by the portable terminal 101 and stored in the memory at the place where the radiation measuring apparatus 100 has acquired the radiation-related data. Then, the position information becomes the position information of the place where the data related to radiation is acquired as it is.

  Further, if the mobile terminal 101 has a camera function, the location where the radiation measurement data is acquired by the radiation measuring apparatus 100 according to the present embodiment is photographed, and the photograph data is stored in the memory together with the radiation data. Can do.

The mobile terminal 101 has a function as a relay base, and preferably has a communication function capable of connecting to the Internet 103 via a mobile phone network or a network communication network compliant with WiFi.
The mobile terminal 101 has an application program for receiving data related to radiation from the radiation measuring apparatus 100 of the present embodiment and transmitting the data and position information acquired by the GPS 102 automatically or manually via the Internet 103. It is necessary to install it beforehand. Of course, it is assumed that the mobile terminal 101 has a function capable of executing data communication according to the application program.

For example, an external server 104, another portable terminal 106, a personal computer 107, and the like can be transmitted to the data from the portable terminal 101 via the Internet 103. Among these, data can be sent to other portable terminals 106 and personal computers 107 using, for example, an e-mail function.
As will be described later, the external server 104 has a function of discriminating abnormalities of radiation based on data including position information sent from the portable terminal.
Further, the external server 104 uses a web-based map display service application such as a Google map application provided by Google, Inc., for example, to obtain the position acquired by the mobile terminal 101 on the map. Information regarding radiation can be displayed at a point corresponding to the information so that the general public can view it.

[Determination of transmission data falsification]
FIGS. 11 to 14 are diagrams for explaining a function of determining whether or not transmission data has been tampered with in a data communication system.
As shown in FIG. 11, the radiation measuring apparatus 100 uses, as parameters, an encryption key set in advance for each individual radiation measuring apparatus, a device ID unique to the device, measurement data, and data (time data) related to measurement time. A device hash value is generated for each measurement (ie, for each individual measurement data).
Here, the encryption key and the device ID are stored in the memory 62 in advance (see FIG. 4). The measurement data is output data from the central processing unit 61 (data processing unit). In the present embodiment, the timing at which the central processing unit 61 inputs a signal from the counter 12, the A / D converter 25, or the counter 42 is set as the measurement start time, and time data regarding the measurement time is output from the timer 71 at the timing. The As the time data, an appropriate time related to measurement, such as an appropriate time while the data processing unit performs data processing, an end time when the data is output from the data processing unit, or the like can be used.
The device hash value is generated by the central processing unit 61 with an algorithm based on SHA-256.
Then, the radiation measurement apparatus 100 collects the apparatus ID, measurement data, time data, and generated apparatus hash unique to the apparatus as apparatus output data and transmits the apparatus output data to the outside. However, the encryption key is not transmitted from the radiation measurement apparatus 100.
The device output data is received by the portable terminal 101 possessed by the user of the radiation measuring apparatus 100.

  Next, as illustrated in FIG. 12, the mobile terminal 101 includes a preset terminal number (for example, a telephone number or a serial number), location information acquired from the GPS 102, data regarding the acquisition date and time of the location information, and the mobile terminal The data of the field photograph taken with the camera incorporated in 101 is added to the device output data and transmitted as terminal additional data. In addition, the portable terminal 101 has a function of generating a terminal hash value using the apparatus hash value received from the radiation measuring apparatus 100 and the terminal additional data as parameters. The generated terminal hash value is also added to the device output data and transmitted.

The external server 104 collectively receives device output data, terminal additional data, and a terminal hash value from the mobile terminal 101. As shown in FIG. 13, the external server 104 stores the encryption key set in each radiation measurement apparatus 100 to which data is sent in advance in a storage medium (not shown). Then, the device ID, measurement data, and time data included in the received device output data, and the encryption key corresponding to the radiation measurement device 100 that transmitted the device output data are generated by the radiation measurement device 100 as parameters. A device hash value for comparison is generated with the same algorithm.
If the received data has not been tampered with, the comparison device hash value is the same as the device hash value generated by the same algorithm using the same data as a parameter. On the other hand, if the received data has been tampered with, the generated comparison device hash value is different from the device hash value included in the received data. As a result, it can be determined whether or not the data has been tampered with in the middle, and the high reliability of the received data can be compensated.

Further, as shown in FIG. 14, the external server 104 receives the received terminal additional data (terminal number, location information, location information acquisition date and field photo), and the comparison device hash value generated as described above. Is used as a parameter, and a comparison terminal hash value is generated by the same algorithm as that generated by the mobile terminal 101.
If the received data has not been tampered with, the comparison terminal hash value is the same as the terminal hash value generated by the same algorithm using the same data as a parameter. On the other hand, when the received data has been tampered with, the generated comparison terminal hash value is different from the terminal hash value included in the received data. This makes it possible to determine whether or not the data has been tampered with. In particular, if the comparison device hash value described above is the same value as the device hash value, but the generated comparison terminal hash value is different from the terminal hash value included in the received data, the comparison device hash value is downstream of the mobile terminal 101. It can be determined that it has been tampered with, and traceability can be secured.

[Distinguishing radiation abnormalities with an external server]
FIG. 15 is a flowchart for explaining a radiation abnormality determination function provided in an external server.
The server 104 accumulates measurement data transmitted to the central processing unit 61 of the radiation measurement apparatus 100 possessed by many users and received via the portable terminal 101. The reception status of measurement data is constantly monitored (step S1), and each time new measurement data is received (step S2), data analysis is performed (step S3), and radiation abnormalities are detected based on the analysis results. The presence / absence of a point is determined (step S4). The data analysis and the presence / absence determination of abnormal points performed here can improve analysis / determination accuracy by combining a plurality of analysis methods such as multivariate normal distribution analysis and mesh division analysis.

In the mesh division analysis, for example, as shown in FIG. 16, the entire radiation measurement area is divided into mesh shapes, the radiation dose is analyzed for each mesh (block), and compared with the analysis values of adjacent meshes. This is a method for determining an abnormality.
In addition, as a means for analyzing a large amount of data added every moment in real time, an abnormal point can be detected by using a multivariate normal distribution analysis method and a Mahalanobis generalized distance.
Radiation measurement values can be regarded as an extended normal distribution in a four-dimensional space with time, space (latitude, longitude), and individuals as variables. An abnormal state can be determined by seeing how far each measured value is from the center of the distribution of data obtained from all measured values.

  Next, in this embodiment, a step of determining whether there is an abnormality in the individual of the radiation measuring apparatus 100 is inserted (step S5). That is, when abnormal measurement data is sent from only one of a plurality of radiation measurement apparatuses 100 existing at a short distance, it is determined that the radiation measurement apparatus 100 is out of order (step S6). .

  Furthermore, the server 104 monitors the amount of change in radiation over time based on the measurement data from the radiation measurement apparatus 100 (step S7), and when the amount of change per unit time is small (that is, constantly) In the case of showing an abnormal value), it is determined that the area where the radiation measuring apparatus 100 exists is contaminated with radiation. In this case, paying attention to a plurality of measurement data in the region, the range of the regional range indicating the abnormal value of the radiation is examined (step S8). When the abnormal value detection range is dispersed in a wide region, Then, it is determined that wide-area contamination has occurred in the area (step S9). On the other hand, when the radiation measuring apparatus 100 to which data indicating radiation abnormality is concentrated in an area narrower than the predetermined range, it is determined that a hot spot exists in the area (step S10).

  Further, in the present embodiment, when the amount of change in radiation per unit time is large, accidents such as leakage of radiation and illegal dumping of radioactively contaminated substances occur in the area where the radiation measurement apparatus 100 exists. Inserts a step to guess that there was. That is, paying attention to a plurality of measurement data in the region, the range of the regional range indicating the abnormal value of radiation is examined (step S11). When the detection range of the abnormal value is dispersed in a wide region, the region It is determined that an accident such as leakage of radioactivity has occurred (step S12). On the other hand, when the radiation measuring apparatus 100 to which the data indicating the abnormality of radiation is sent is concentrated in an area narrower than the predetermined range, it is determined that there is an illegal dumping of a radioactively contaminated substance in the area. (Step S13).

  Note that the amount of change in radiation over time in step S7 is monitored with reference to time data sent from the radiation measuring apparatus 100. In addition, whether the regional range is wide or narrow in step S8 or step S11 is determined with reference to data related to position information sent from the mobile terminal 101.

  In this way, the measurement data sent from the radiation measuring apparatus 100 is analyzed to determine the abnormal point, the cause of the abnormality is further determined, and the situation is sent to the web-based map display service application and displayed on the map. The information is displayed (step S14) and recorded in the database of the server 104 (step S15).

  If a large number of measurement data are continuously sent from the radiation measurement apparatus 100 owned by many users, the cause of the radiation abnormality described above can be investigated quickly and with high accuracy, and the determination result is displayed on the web. If it is displayed on the map of the base map display service application and used for viewing by the general public, many people can obtain a material for making an accurate judgment on radioactive contamination.

In addition, this invention is not limited to embodiment mentioned above, Of course, various deformation | transformation implementation and application implementation are possible for others.
The above-described data communication system is separated from the radiation measurement apparatus according to the present invention as necessary to constitute a unique invention, and is applied to various radiation measurement apparatuses and various communication apparatuses having a function of transmitting data. You can also
The configuration of the data communication system in that case is as follows.

[Configuration 1]
A data communication system for sending data output from a radiation measurement device (or communication device) to an external server,
The radiation measurement device (or communication device) uses a parameter including an encryption key preset for each individual radiation measurement device (or communication device) and data output from the radiation measurement device (or communication device). A device hash value generation means for generating a unique hash value (device hash value) for each individual data output from the radiation measurement device (or communication device),
Data transmission means for transmitting data including the data output from the radiation measurement device (or communication device) and the device hash value,
The encryption key is not transmitted to the outside from the radiation measurement device (or communication device),
The server is sent from the encryption key set in each radiation measurement device (or communication device) to which data is sent in advance, and from the encryption key and the radiation measurement device (or communication device). Means for generating a hash value (comparison device hash value) in the same manner as the radiation measurement device (or communication device) based on the collected data, and the generated comparison device hash value is sent from the radiation measurement device (or communication device). A data communication system comprising: means for determining whether or not the data transmitted from the radiation measurement apparatus (or communication apparatus) has been tampered with in comparison with the received apparatus hash value.

[Configuration 2]
A portable terminal that receives data sent from the radiation measurement device (or communication device) and transmits the data to the server via the Internet;
The portable terminal is
Receiving means for receiving data sent from the radiation measuring device (or communication device);
Based on a parameter including the device hash value included in the data transmitted from the radiation measurement device (or communication device) and data added by the mobile terminal, a hash value (terminal hash unique to the mobile terminal) Terminal hash value generation means for generating (value),
Terminal data transmission means for collectively transmitting data sent from the radiation measurement apparatus (or communication apparatus), the terminal hash value, and data added by the portable terminal to the server,
The server receives a means for generating a hash value (comparison terminal hash value) based on data received from the portable terminal, and the generated comparison terminal hash value from the portable terminal. And a means for discriminating whether or not the data sent from the portable terminal is falsified as compared with the terminal hash value.

1: device main body, 2: operation unit, 3: display unit, 4: protective cover, 5: gripping unit, 6: connector 10: GM detector, 10a: radiation incident surface, 11: comparator, 12: counter,
20: Compound semiconductor detector, 21: Integration amplifier, 22: Second amplifier, 23: Selector, 24: Variable gain amplifier, 25: A / D converter,
30: Scintillation detector, 31: Integration amplifier, 32: Switch,
40: 3He neutron detector, 41: comparator, 42: counter,
50: High voltage power supply circuit, 51: CWC,
60: 1 chip microcomputer, 61: central processing unit, 62: memory 71: timer, 72: communication module, 73: external connection interface,
101: Mobile terminal, 102: GPS, 103: Internet, 104: External server, 106: Other mobile terminals, 107: Personal computer

Claims (12)

A detector that detects the energy of radiation and outputs an analog electrical signal having a wave height corresponding to the energy;
An integrating amplifier that amplifies and outputs the analog electrical signal output from the detector;
An A / D converter for digitally converting an output signal from the integrating amplifier at a preset sampling interval;
A data processing unit that performs data processing on the digitally converted electrical signal and determines energy of radiation input to the detector;
The sampling interval of the A / D converter is 1 μsec or less,
The integrating amplifier discharges the output signal over a time longer than the sampling interval of the A / D converter, and the value at which the decrease of the peak value of the output signal is suppressed within 5% in the sampling interval of the A / D converter. Yes to set a two-time constant,
The output signal from the integrating amplifier, a radiation measuring device which is characterized that you input to the A / D converter without the waveform shaping. The radiation measuring apparatus according to claim 1, wherein the A / D converter and the data processing unit are configured by a microcomputer made of one chip. A second detector composed of a Geiger-Muller detector;
A comparator that outputs a pulsed signal when the analog electrical signal output from the second detector exceeds a preset threshold value;
A counter that counts the number of signal outputs from the comparator,
Wherein the data processing unit, the radiation measuring device according to claim 1 or 2, characterized in that to determine the radiation detection number per unit time based on an output from said counter. The data processing unit is configured to obtain radiation detection number data per unit time obtained based on the output from the second detector, by a conversion coefficient specified by the energy of the radiation obtained based on the output from the detector. The radiation measuring apparatus according to claim 3 , further comprising a function of converting to dose equivalent rate data representing a degree of influence of radiation on a human body. Equipped with a memory that stores in advance a radioisotope database in which the peak positions and intensities of radiation energy are registered for each nuclide,
The data processing unit obtains a spectrum of radiation based on an output from the detector, performs a smoothing process on the spectrum, then performs a background removal process to extract a peak component, and a peak position from the extracted peak component The nuclide identification process is performed by comparing the peak position and intensity with the radioisotope database, the conversion coefficient is identified from the identified nuclide, and the conversion coefficient is determined from the second detector. The radiation measurement apparatus according to claim 4 , further comprising a function of converting the number of detected radiation per unit time obtained based on the output of the above into data of a dose equivalent rate representing a degree of influence of radiation on a human body. Equipped with a memory that stores in advance a radioisotope database in which the spectrum of radiation is registered for each nuclide,
The data processing unit obtains a spectrum of radiation based on an output from the detector, performs a smoothing process on the spectrum, and then performs a nuclide identification process by comparing the entire spectrum with the radioisotope database. Dose equivalence rate representing the degree of influence of radiation on the human body by identifying the conversion coefficient from the nuclide and using the conversion coefficient to determine the number of detected radiation per unit time based on the output from the second detector. The radiation measuring apparatus according to claim 4 , further comprising a function of converting the data into the data.   The radiation measuring apparatus according to claim 1, wherein a compound semiconductor detector is used as the detector. A data communication system for sending data output from the data processing unit in the radiation measuring apparatus according to any one of claims 1 to 7 to an external server,
The radiation measuring device comprises:
A unique hash value (apparatus for each piece of data output from the data processing unit based on parameters including an encryption key set in advance for each individual radiation measurement device and data output from the data processing unit Device hash value generation means for generating a hash value),
Data transmission means for transmitting data including data output from the data processing unit and the device hash value, and
The encryption key is not transmitted to the outside from the data transmission means,
The server is similar to the radiation measuring apparatus based on the means for storing in advance the encryption key set in each radiation measuring apparatus to which data is sent and the data sent from the encryption key and the radiation measuring apparatus. Means for generating a hash value (comparison device hash value) and data sent from the radiation measurement device by comparing the generated comparison device hash value with the device hash value sent from the radiation measurement device And a means for discriminating whether or not tampering has occurred. Receiving data sent from the radiation measurement device, comprising a mobile terminal that transmits to the server via the Internet,
The portable terminal is
Receiving means for receiving data sent from the radiation measuring device;
A hash value (terminal hash value) unique to the portable terminal is generated based on a parameter including the device hash value included in the data transmitted from the radiation measuring apparatus and data added by the portable terminal. A terminal hash value generation means;
Terminal data transmission means for collectively transmitting data sent from the radiation measurement apparatus, the terminal hash value, and data added by the portable terminal to the server,
The server receives a means for generating a hash value (comparison terminal hash value) based on data received from the portable terminal, and the generated comparison terminal hash value from the portable terminal. 9. The data communication system according to claim 8, further comprising: means for determining whether or not the data transmitted from the portable terminal is falsified by comparing with the terminal hash value. A radiation abnormality determination system that determines abnormality of radiation based on data sent from a large number of users who possess the radiation measuring apparatus according to any one of claims 1 to 7,
The radiation measuring apparatus adds the time data to data output from the data processing unit to means for outputting data (time data) relating to measurement time and a portable terminal possessed by the user together with the radiation measuring apparatus. Data transmission means for transmitting,
The mobile terminal has a function for acquiring position information using GPS, and adds the position information to the data sent from the radiation measuring apparatus and transmits it to an external server via the Internet. With the features of
The external server includes a function of determining a radiation abnormality based on data including position information transmitted from the portable terminal.   In the server, the data output from the data processing unit of the radiation measurement apparatus possessed by a large number of users indicates an abnormality of radiation, and the amount of change in radiation over time is smaller than a predetermined threshold, 11. When the radiation measuring apparatus to which the data indicating the abnormality of the radiation is sent is concentrated in an area narrower than a predetermined range, it is determined that a hot spot exists in the area. Radiation abnormality discrimination system.   In the server, the data output from the data processing unit of the radiation measurement apparatus possessed by a large number of users indicates an abnormality of radiation, and the amount of change in radiation over time is smaller than a predetermined threshold, In addition, when the radiation measurement devices to which data indicating the abnormality of the radiation is transmitted are dispersed in an area wider than a predetermined range, it is determined that wide-area contamination has occurred in the area. Item 10. A radiation abnormality determination system according to item 10 or 11.

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