JP2015175803A - radiation distribution measurement system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of a conventional technology, that is, to provide a radiation distribution measurement system capable of comprehensively investigate an amount of radiation without leaving any measurement omission place with an individual area such as a dwelling house or a school as a target.SOLUTION: A radiation distribution measurement system configured to enable an investigator to measure the radiation distribution of a target place while walking includes: radiation measurement means; position information acquisition means; autonomous navigation positioning means; position information correction means; storage means; and display means. The radiation measurement means is configured to acquire the physical amount of the radiation as a radiation measurement value, and the position information acquisition means is configured to acquire the position information of an investigation spot by receiving an output wave. Also, the autonomous navigation positioning means is configured to estimate the locus of the investigator by an autonomous navigation method and to acquire the position information of the investigation spot, and the position information correction means is configured to correct the position information on the basis of the position information by the position information acquisition means and the position information by the autonomous navigation positioning means.

Description

  The present invention relates to a technique for measuring the distribution of radiation in a target region. More specifically, the radiation distribution is obtained by measuring radiation dose while walking and acquiring coordinate information of a measurement position. The present invention relates to a radiation distribution measurement system that can be obtained.

  In recent years, environmental destruction caused by global warming has progressed, and the preservation of the global environment has become a global problem. In 1997, the Kyoto Protocol was signed, and many countries are actively tackling this issue, including the establishment of greenhouse gas reduction targets. In Japan as well, measures to reduce greenhouse gases have been implemented by public and private sectors, one of which is nuclear power generation. In addition to the power generated by nuclear power generation, the amount of greenhouse gas emissions is much smaller than that of so-called fossil energy generation, so a shift from the previous power generation method to this method has been made.

  On the other hand, Japan is known as a country where earthquakes occur frequently, and major earthquakes such as the Tohoku-Pacific Ocean Earthquake, the Hyogoken-Nanbu Earthquake, and the Niigata-ken Chuetsu Earthquake have occurred and have suffered enormous damage each time. In the previous Great East Japan Earthquake, there was an accident in which a large amount of radioactive material leaked due to the damage caused by the tsunami and further damage to the reactor at the Fukushima nuclear power plant.

  The radioactive material leaked from the nuclear power plant spread not only in the vicinity but also in a wide area. This is thought to be due to the radioactive substance adhering to the aerosol or the like, and the aerosol or the like was used as a transport carrier to take the radioactive substance far away and fall to the ground due to rain water or the like. In any case, the effects of accidents at nuclear power plants are wide-ranging, and the Special Measures Act on Radioactive Substance Contamination Measures Concerning the Environmental Pollution Status of Accident-derived Radioactive Substances More than 100 municipalities are designated as “Region”.

  Even if radioactive materials are diffused over a wide area, the radiation dose varies depending on the location, and some regions show extremely high radiation doses, while others show radiation doses that do not affect the environment. In areas with high radiation doses, the effects on the human body must be considered. Currently, each residential area is restricted using the radiation dose (mSv / year) for one year as an index. 50 mSv or more is a difficult return home area, 20 mSv or more is a residential restriction area, and 1 mSv or more is an evacuation order cancellation preparation area. There are 7 municipalities that have difficulty returning home, 8 municipalities that have restricted residence, and 11 municipalities that have difficulty preparing for clearing difficult orders. It is an urgent issue to take appropriate decontamination measures for such restricted areas and to release all restrictions at an early stage.

  By the way, although the whole area does not show a very high radiation dose, there are cases where it shows a very high radiation dose locally. Or the case where a low radiation dose is partially shown even if it is a residence restriction area is also considered. It is extremely important for life safety to extract a spot that shows a high radiation dose locally compared to the surrounding area (hereinafter referred to as “hot spot”). Extraction of the point indicating the dose occurs in a situation where the decontamination work is reduced and there are not enough places to store the contaminated soil generated by the decontamination (such as temporary storage and intermediate storage facilities). As a result, the amount of contaminated soil is reduced, which is extremely beneficial.

  As described above, when the local radiation dose is grasped, a method is used in which partial measurement is performed by dividing into a narrow range, not the entire measurement by an aircraft or the like. In fact, in Fukushima Prefecture, more than 200,000 houses have been surveyed one by one, and decontamination measures are being pursued in accordance with the results. When measuring the radiation dose of a house, follow the “Guidelines for Handling Locally Contaminated Sites with Radioactive Substances—Ministry of the Environment” (hereinafter simply referred to as “Guidelines for Handling Contaminated Sites”). After extracting a predicted part (hereinafter referred to as “contamination predicted part”), the measurement is performed mainly on the part. This is to find “locally contaminated spots” that are actually contaminated as soon as possible, and examples of the predicted rain spots include rain gutters, drain outlets, gutters / drains, and rain gutters of buildings.

  However, the extraction of the predicted contamination location is performed by human judgment, and the extraction accuracy depends on the knowledge and experience of the investigator. Considering a large number of research houses, a large number of investigators will make measurements, and therefore, the extraction criteria for the predicted contamination location will be uneven, and as a result, the localized contamination location may not be found correctly. In addition, if the measurement results are not recorded together with the position information, appropriate decontamination measures cannot be implemented. However, while measuring the radiation dose, the position measurement is performed at the same time, and the measurement value and the position information are recorded in association with each other. It is not so easy to do. Actually, the actual measurement position is written on the prepared paper drawing, and as a result, an error or a record omission may occur, but this cannot be confirmed later.

  Therefore, Patent Document 1 proposes a technique for recording position information of measurement points. This technology prepares a portable communication terminal having both positioning means and a camera function, acquires position information with this terminal, and acquires a display unit of a separately prepared radiation measuring instrument as an image. It is possible to take a picture of the value measured in step 1, and store the image in association with the position information.

JP2013-167480A

  As described, there is a possibility that the predicted contamination location may not be extracted properly by the investigation method based on the contamination location countermeasure guideline, that is, the hot spot may not be correctly identified. Alternatively, even if a predicted contamination location is appropriately extracted based on the contamination location countermeasure guidelines, if a hot spot exists in a location different from the predicted contamination location, the hot spot cannot be correctly identified.

  The contamination point countermeasure guideline is “extraction measurement” because it aims at early detection, but “hot area measurement” is still necessary to detect hot spots. In the case of school, the site including the playground is surveyed, and in the case of the residence, the site including the garden is comprehensively investigated. Comprehensive, that is, in order not to leave missing points, it is necessary to investigate the existing and unexamined locations while surveying, for example, dividing the site into a mesh and marking the mesh There is a method to proceed while attaching.

  However, in order to divide the site into a mesh, it is necessary to survey, and to actually show the mesh, it is necessary to tape or draw a line. Considering 200,000 houses in the prefecture, it is not realistic. Moreover, even if the mesh can be shown, if a person performs the process of marking the mesh that has been investigated, there is a risk of erroneous writing or omission of records, which may result in missing points. . Since Patent Document 1 records measurement values and position information in association with each other, it is possible to check a missing measurement location after the completion of measurement work, which is considered to be a powerful technique for comprehensive investigation. However, it is troublesome to image the display unit of the radiation measuring instrument each time it is measured, and it is also conceivable that an image that is so unclear that a numerical value cannot be confirmed is acquired. In addition, it is known that an error of about 3 m is caused by independent positioning by GPS (Global Positioning System) shown in Patent Document 1, and if there is a fault such as a roof or garden tree, a point greatly deviated from the site is used as a coordinate. There is also a case to output. Therefore, Patent Document 1 is also not a technique suitable for exhaustive investigation without leaving missing points.

  The problem of the present invention is to solve the problems of the prior art, that is, radiation distribution capable of comprehensively investigating the radiation dose without leaving missing points in individual areas such as houses and schools To provide a measurement system.

  The present invention improves positioning accuracy by combining a positioning method such as a satellite positioning system (GNSS: Global Navigation Satellite System) and autonomous navigation by walking, and associates a radiation distribution by associating a high-accuracy position coordinate with a radiation dose. This is an invention made based on an idea that has not existed in the past.

  The radiation distribution measurement system of the present invention measures a radiation distribution of a measurement target site while an investigator walks. Radiation measurement means, position information acquisition means, autonomous navigation positioning means, position information correction means, storage means, It is a system provided with a display means. The radiation measurement means acquires the physical quantity of the radiation at the investigation point as a radiation measurement value, and the position information acquisition means acquires the position information of the investigation point by receiving an output wave from another. The autonomous navigation positioning means acquires the position information of the survey point by estimating the trajectory that the investigator walked by autonomous navigation, and the position information correction means is the position information acquired by the position information acquisition means and the autonomous navigation positioning. The position information of the survey point is corrected based on the position information acquired by the means. The storage means stores the correction position information obtained by the position information correction means in association with the radiation measurement value of the investigation point corresponding to the correction position information, and the display means is based on the correction position information of the investigation point. The radiation measurement value is displayed. As a result, the investigator acquires radiation measurement values at a plurality of survey points while carrying the radiation measurement means, position information acquisition means, autonomous navigation positioning means, and display means, so that the radiation distribution map of the measurement target site can be obtained. Can be obtained.

  The radiation distribution measurement system of the present invention can be a system further including missing point extraction means. The missing measurement point extraction means divides the measurement target area into a plurality of divided areas, associates each divided area with the radiation measurement value acquired in the divided area, and has an associated radiation measurement value. A divided area is a measured area, a divided area having no associated radiation measurement value is an unmeasured area, and an unmeasured area is a missing place. In this case, the display means can display the missing part.

  In the radiation distribution measurement system of the present invention, an unmeasured area having a caution area around it can be set as a missing position. In this case, the missing measurement location extraction means sets the measured region associated with the radiation measurement value equal to or greater than the predetermined threshold as the attention region, and the unmeasured region having the attention region around it as the missing measurement location.

  The radiation distribution measurement system of the present invention can be a system further equipped with a glasses-type wearable terminal. This glasses-type wearable terminal is equipped with position information acquisition means, autonomous navigation positioning means, and display means.

  The radiation distribution measurement system of the present invention may be a system that displays augmented reality in which the display means of the glasses-type wearable terminal overlaps the real space and the radiation measurement value.

The radiation distribution measurement system of the present invention has the following effects.
(1) The radiation dose can be comprehensively investigated without leaving missing points in individual areas such as houses and schools. As a result, it is possible to extract all points requiring attention including hot spots.
(2) Since coordinates are obtained by performing autonomous navigation in addition to a positioning method such as GNSS, the position of the measurement point can be acquired more accurately than in the past.
(3) Since the measurement results of the survey target area can be output as a radiation distribution map (map), it can be used for the progress management of the survey and also used as a document when explaining the decontamination countermeasure status to the residents. Can do.

The block diagram which shows the main structures of the radiation distribution measuring system of this invention. The flowchart which shows the flow of the main processes of the radiation distribution measurement system of this invention. The top view which shows the housing premises which are investigation object sites. Radiation distribution map created based on survey results. The model figure which divided | segmented the residential site which is an investigation object site into several division area. The radiation distribution map which shows the measured area and the unmeasured area in the middle of an investigation. Radiation distribution map with warning display of missing points.

  An example of an embodiment of the radiation distribution measurement system of the present invention will be described with reference to the drawings.

1. Overall Overview First, the main configuration of the radiation distribution measurement system of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing the main configuration of the present invention. As shown in this figure, the radiation distribution measurement system includes at least a radiation measurement unit 100, a position information acquisition unit 200, an autonomous navigation positioning unit 300, a position information correction unit 400, a storage unit 500, and a display unit 600. Moreover, in addition to these, the missing location extraction means 700 can also be provided.

  The radiation measuring means 100 includes a radiation measuring instrument 101 that actually measures a physical quantity of radiation, and a measurement value transmitter 102 that transmits a measurement value obtained by the measurement (hereinafter referred to as “radiation measurement value”). . The position information acquisition unit 200 includes, for example, an output wave receiver 201 that receives a signal output from a satellite (hereinafter referred to as “output wave”), and a current position (position at the time of reception) based on the received information. The coordinate calculating means 202 for calculating is included. Autonomous navigation positioning means 300 includes a trajectory measuring device 301 that measures a moving direction and a moving distance (hereinafter collectively referred to as “trajectory information”) of a walking investigator, and a current position based on the measured trajectory information. Coordinate calculation means 302 for calculating is included. Note that both the position information acquisition means 200 and the autonomous navigation positioning means 300 output the current position of the investigator as “position information”, but here, for the sake of convenience, what is calculated by the position information acquisition means 200 is distinguished. The “first position information” and the information calculated by the autonomous navigation positioning means 300 are referred to as “second position information”.

  For example, a place with a roof or a standing tree is difficult to receive an output wave from a satellite, and as a result, the first position information calculated by the position information acquisition unit 200 may include a large error. The position correction unit 400 corrects position information that is not reliable in this way to position information that is more reliable. Specifically, when it is determined that the first position information includes a large error, the corrected position information (hereinafter referred to as the first position information that is reliable) and the trajectory information obtained by the trajectory measuring machine 301 are used. , “Corrected position information”).

  The radiation measurement value and the corrected position information are associated with each other based on the acquired time. For example, the measurement time at which the physical quantity of radiation is measured is compared with the measurement time of the correction position coordinates, and the radiation measurement value having the closest time is associated with the correction position information. The combination of the radiation measurement value and the correction position information associated here is stored in the storage unit 500 as “map information”.

  The display unit 600 visually represents the map information stored in the storage unit 500. Since the map information includes position information, it can be displayed as a radiation distribution map in the survey target area. Specifically, the topographic map of the survey target site is used as a base map, and the survey point and the physical quantity of radiation are displayed on this base map. As will be described later, by providing the missing point extraction means 700, the missing point can be displayed. Thereby, since measurement omission can be grasped during measurement, rework such as re-measurement at a later date can be prevented.

  The radiation distribution measurement system of the present invention can be manufactured as a dedicated one, but a general-purpose computer device can also be used. This computer apparatus can be configured by a personal computer (PC), a tablet PC such as iPad (registered trademark), a smartphone, or a PDA (Personal Data Assistance). The computer apparatus includes a processor such as a CPU and a memory such as a ROM and a RAM, and further includes an input unit such as a mouse and a keyboard and a display (display unit 600). In addition, although it inputs from devices, such as a mouse | mouth and a keyboard, if it is a general PC, it is often input by operation (a tap, a pinch in / out, a slide, etc.) using a touch panel with a tablet PC or a smart phone.

  When a general-purpose computer device is used, the coordinate calculation means 202 of the position information acquisition means 200, the coordinate calculation means 302 of the autonomous navigation positioning means 300, the position information correction means 400, and the storage means 500 shown in the dashed frame in FIG. The display means 600 may be mounted on a computer device. In particular, when a smartphone is used, an output wave receiver 201 and a trajectory measuring device 301 can be mounted in addition to the broken line frame in FIG. In addition, it is also possible to use a glasses-type wearable terminal instead of the smartphone. In this case, the position information acquisition means 200, the autonomous navigation positioning means 300, the position information correction means 400, the storage means 500, and the display means 600 are mounted. be able to.

  Next, the main processing flow of the radiation distribution measuring system of the present invention will be described with reference to FIG. FIG. 2 is a flow chart showing the main processing flow of the present invention, showing the actions (processes and processes) to be performed in the center column, and the left column showing the input information necessary for the actions and the means to be used. The right column shows the output information generated from the action.

  First, go to the site to be surveyed, and confirm the survey plan prepared in advance. The investigator carries the necessary equipment and conducts the survey at each point of the survey target area while walking. This will be described in detail below. When the investigator moves to a predetermined measurement point, the physical quantity of radiation is measured by the radiation measuring means 100 to obtain a radiation measurement value (Step 10). In addition to the radiation measurement, the position information acquisition unit 200 acquires the first position information (Step 20), and the autonomous navigation positioning unit 300 acquires the second position information (Step 30). The acquired first position information and second position information are input to the position information correction means 400, the correction position information is output (Step 40), and the radiation measurement value and the corresponding correction position information are associated with each other to obtain map information. Is stored (Step 50).

  When the survey at the first survey point is completed, the user walks to the next survey point and repeats Step 10 to Step 50. Note that the creation of map information (Step 50) may be processed whenever the survey at the survey point is completed as described above, or may be processed collectively after the survey at all the points is completed. When the surveys at all points are completed and map information is obtained at all the survey points, a radiation distribution map is created based on the map information and displayed on the display means 600 (Step 70). In this case as well, the radiation distribution map can be displayed when the surveys at all the points are completed, and the radiation distribution map can be displayed whenever necessary at each measurement point.

  When displaying a radiation distribution map as a mid-course during an on-site survey, it is preferable to be able to prevent missing surveys if it is possible to grasp the missing measurement points. In the flow of FIG. 2, Step 60 is a process of extracting missing points. In this case, a topographic map (plan view) of the survey target area is prepared in advance. This topographic map can be processed by a computer and is created in a data format that can be displayed on the display means 600. Based on the topographic map, the survey area is divided to obtain a plurality of divided areas (Step 61). Examples of the division method include mesh division using a square lattice, but the division method is not limited to this, and the division can be arbitrarily performed according to the target terrain.

  When the divided areas are obtained, the map information in each divided area is associated. Then, the radiation measurement value in the map information associated with the divided area is set as a representative value of the divided area (Step 62). When two or more pieces of map information exist in one division area, a representative value can be appropriately determined by selecting a larger (or smaller) radiation measurement value or adopting an average value. The radiation measurement value representing the divided area is referred to as “mesh information” here.

  When mesh information is obtained in the survey target area, it is divided into divided areas having mesh information and divided areas having no mesh information. This means whether or not the survey has been carried out with the mesh, so that each divided area is classified as either “unmeasured area” or “measured area” (Step 63). If an unmeasured area is extracted (Step 64), it can be specified as a missing place (Step 66). Alternatively, instead of setting all unmeasured areas as missing places, unmeasured areas where attention areas exist in the vicinity can be extracted (Step 65), and can be specified as missing measurement places (Step 66). Here, the attention area is a divided area (measured area) having mesh information (radiation measurement values) exceeding a predetermined threshold value. The area is specified as a missing place, but if the surrounding radiation measurement value is low, it is not specified as a missing place.

  Hereinafter, main elements constituting the present invention will be described in detail.

2. Radiation Measurement The radiation measurement means 100 used in the present invention measures some physical quantity based on radiation. As this physical quantity, a dose (Sv) such as a beta ray or a gamma ray, or a radioactivity (Bq) inherent in a radioactive substance. Can be mentioned. The radiation measuring means 100 is preferably a small portable type so that a pedestrian can carry it, and a so-called survey meter can be used. The survey meter can be appropriately selected according to the type of radiation to be detected, such as one using a Geiger-Muller counter, one using a scintillation type, one using an ionization chamber, or one using a semiconductor.

  When the investigator investigates while walking, a pole equipped with a survey meter can be used. For example, if you want to measure the air dose rate (μSv / h) of 1m above the ground, if you keep the survey meter fixed at a position of 1m from the bottom of the pole, you do not need to survey the survey height each time you measure it. Can be investigated. Alternatively, if the survey meter is fixed at a position 1 cm from the lower end of the pole, the surface dose rate can be measured. Of course, it is also possible to measure the air dose rate (1 m above the ground) and the surface dose rate at the same time by fixing survey meters at two locations 1 m and 1 cm from the lower end of the pole.

3. Positioning Using Output Waves As described, the position information acquisition means 200 calculates the current position by receiving output waves, and a typical example is GNSS such as GPS (Global Positioning System). . In addition, a positioning method that uses an access point of a wireless LAN such as Wi-Fi, a positioning method that uses visible light communication that transmits high-speed blinking of an LED as a signal, a positioning method that uses sound waves, and IMES ( Any device that can acquire the position information of the survey point by receiving the output wave output from the transmitting means, such as the Indoor Messaging System, can be used as the position information acquiring means 200.

4). Positioning by Autonomous Navigation Autonomous navigation is a technique for recording the movement path (trajectory information) of a person who moves from the starting point (here, the investigator) and obtaining coordinates after movement based on the trajectory information and the starting point coordinates. Therefore, a trajectory measuring machine 301 for acquiring trajectory information and a coordinate calculation means 302 for obtaining coordinates are required. Further, in order to obtain the coordinates by the coordinate calculation means 302, at least the moving direction and moving distance when the investigator moves are necessary as the trajectory information, that is, the trajectory measuring machine 301 can measure the direction and distance while moving. Must be a thing.

  Examples of the device that measures the azimuth while moving (hereinafter, referred to as “azimuth meter”) include a gyro that measures angular velocity, a geomagnetic sensor that detects geomagnetism (for example, an electronic compass), and the like. On the other hand, as a device that measures a distance while moving (hereinafter referred to as a “distance meter”), an acceleration sensor that measures acceleration, or a DMI (Distance Measuring Indicator) that measures a distance from rotation of a wheel (tire). Can be illustrated. The azimuth meter and the distance meter as the trajectory measuring machine 301 can be prepared as separate bodies, respectively, or an integrated type equipped with both can be used. For example, smartphones that mainly include an electronic compass and an acceleration sensor are the mainstream, and if this is used as the trajectory measuring device 301, a researcher can easily carry it and is extremely suitable. Further, if the coordinate calculation means 302 is a program executed by a computer and is incorporated in a smartphone, the integrated autonomous navigation positioning means 300 including the trajectory measuring device 301 and the coordinate calculation means 302 is further preferable.

5. Correction of Position Information As described above, the first position information obtained by the position information acquisition unit 200 may include a large error, and does not always give accurate coordinates. On the other hand, the second position information obtained by the autonomous navigation positioning means 300 has a feature that the position information can be acquired without depending on the local environment (for example, an environment with radio wave interference) like the position information acquisition means 200, but the moving distance. It also has the disadvantage of accumulating errors depending on the situation.

  The position correcting unit 400 obtains more reliable position information, that is, corrected position information by using both values of the first position information and the second position information. For example, when it is determined that the first position information is a reliable value, the first position information is used as the corrected position information as it is, and when it is determined that the first position information is an unreliable value, the first reliable first information is determined. The corrected position information is calculated based on the position information and the trajectory information obtained thereafter. Alternatively, when the first position information is determined to be a reliable value, the average value of the first position information and the second position information is used as the corrected position information, and when the first position information is determined to be an unreliable value, The second position information is used as corrected position information as it is. In addition, various corrected position information can be obtained based on the first position information and the second position information. Whether or not the first position information is reliable can be determined by determining that the distance from the most recent first position information is within a threshold, or within a predetermined range (such as within the range of the survey target). It can be determined by using an index that it is within the range, or can be determined by various other methods.

6). Radiation distribution map display The storage means 500 stores the radiation measurement values sent from the measurement value transmitter 102 of the radiation measurement means 100 and the corrected position information obtained by the position correction means 400. At this time, a predetermined radiation measurement value and predetermined correction position information are associated with each other based on the measurement time and the positioning time, and stored as map information. Specifically, the data is stored in a database (DB) included in the storage unit 500 as a record including an identifier (ID), a radiation measurement value, correction position information, and the like. Usually, since the investigator performs a large number of measurements in one survey target area, a large number of records (that is, map information) are stored in the DB of the storage means.

  FIG. 3 is a plan view showing a residential site which is a survey target site. FIG. 4 is a radiation distribution map (map) created based on the survey results. Since the map information includes position information and radiation measurement values at the point, the radiation distribution can be shown in a map form as shown in FIG. In FIG. 4, the black-colored (♦) survey points indicate a high radiation dose, the gray survey points indicate a moderate radiation dose, and the white-painted (□) survey points indicate a low radiation dose. The radiation distribution map created in this way is displayed on display means 600 such as a display of a computer device, or can be visually grasped by being printed by a printer.

7). Extraction of missing places Missing places are extracted in units of divided areas obtained by dividing the survey area. FIG. 5 is a model diagram in which a residential site, which is a survey target site, is divided into a plurality of divided areas. In this figure, it is divided into 6 rows (1-6) × 9 columns (ai), and 54 divided regions are obtained.

  As shown in FIG. 4, when the investigation target area is sequentially investigated, map information (radiation measurement values, corrected position information) is acquired at each investigation point. The map information is associated with a divided area including the survey point, and mesh information (a representative value of the radiation measurement value) is given to the divided area. A divided area having mesh information is a measured area, and a divided area to which no mesh information is assigned is an unmeasured area.

  FIG. 6 is a radiation distribution diagram (map) showing the measured area and the unmeasured area during the investigation. In this figure, the shaded divided areas are shown as measured areas, and the non-shaded divided areas are shown as unmeasured areas. This figure is a state in the middle of the investigation, and after the investigation is started from the 6a divided area (divided area of 6 rows and a columns), the investigation is currently performed up to the 4i divided area. As shown in this figure, the 6d divided area is investigated at two places, but the 6c divided area on the left side of the 6d divided area is an unmeasured area with no investigation place. Further, the 5e divided area is also investigated at two places, and the 5f divided area on the right side is an unmeasured area. As described above, when the radiation distribution map is displayed on the display unit 600 even during the investigation, it is possible to grasp the missing measurement portion, and thus it is possible to prevent the investigation from being omitted.

  Further, it is possible to positively display a warning on a missing location on the radiation distribution map. FIG. 7 is a radiation distribution diagram (map) in which missing measurement points are displayed as warnings. Like FIG. 6, the 6c divided region and the 5f divided region are unmeasured regions. Further, in this figure, the 4a divided region, the 5b divided region, and the 6b divided region are shown as black attention regions. This attention area is a divided area (measured area) having mesh information (radiation measurement values) exceeding a predetermined threshold as described. An unmeasured area (6c divided area) adjacent to the 6b divided area, which is a caution area, is displayed as a warning (indicated by hatching in this figure) as a missing place. On the other hand, the 5f divided area, which is an unmeasured area, has no warning area as a missing measurement area because there is no attention area around it. In other words, it is conceivable that a high radiation dose is also displayed around the attention area, so that the investigation is promoted by actively warning. Thereby, it can be expected that the decontamination measures to be performed later will be appropriately implemented. Note that the missing point extraction process described so far can be constructed by a program executed by a computer.

8). Eyeglass-type wearable terminal Among the means constituting the radiation distribution measurement system of the present invention, the eyeglass-type equipped with position information acquisition means 200, autonomous navigation positioning means 300, position information correction means 400, storage means 500, and display means 600 A wearable terminal can be used. For example, a computer device that executes a program is provided, a GPS receiver is used as the output wave receiver 201, an acceleration sensor and an electronic compass are used as the trajectory measuring device 301, and a memory that incorporates a DB is used as the storage unit 500. 600 has a display. Even if a spectacle-type wearable terminal is worn, both hands are free, and the investigator can conduct an investigation efficiently.

  Further, augmented reality (AR) can be displayed on the display means 600 by using a glasses-type wearable terminal. Calculate the spatial coordinates actually seen by various sensors (GPS receiver, acceleration sensor, electronic compass, etc.) mounted on the glasses-type wearable terminal, and map information corresponding to the coordinates as icons etc. It is superimposed. At this time, the actual space may be actually viewed with the naked eye, or may be expressed by an image acquired by a camera or the like.

  The radiation distribution measurement system of the present invention can be used for radiation distribution measurement in places where it is difficult to receive radio waves from above, such as farms, orchards, and forests, as well as houses and schools. Considering that a portion showing a high radiation dose can be extracted with certainty, the present invention is not only industrially usable but also a great social contribution.

100 Radiation measurement means 101 Radiation measurement machine 102 (of radiation measurement means) Measurement value transmitter 200 (of radiation measurement means) Position information acquisition means 201 Output wave receiver 202 (of position information acquisition means) (of position information acquisition means) Coordinate calculation means 300 Autonomous navigation positioning means 301 Trajectory measuring device 302 (of autonomous navigation positioning means) Coordinate calculation means 400 (of autonomous navigation positioning means) Position information correction means 500 Storage means 600 Display means 700 Missing point extraction means

Claims (5)

A radiation distribution measurement system that allows an investigator to measure the radiation distribution of a measurement target site while walking,
A radiation measurement means for acquiring a physical quantity of radiation at the survey point as a radiation measurement value;
Position information acquisition means for acquiring position information of the survey point by receiving an output wave from another;
Autonomous navigation positioning means for acquiring position information of the survey point by estimating the trajectory the investigator has walked by autonomous navigation;
Position information correction means for correcting the position information of the survey point based on the position information acquired by the position information acquisition means and the position information acquired by the autonomous navigation positioning means;
Storage means for storing the correction position information obtained by the position information correction means and the radiation measurement values of the corresponding investigation points in association with each other;
Display means for displaying the radiation measurement value of the survey point based on the corrected position information of the survey point,
An investigator acquires radiation measurement values at a plurality of survey points while carrying the radiation measurement means, the position information acquisition means, the autonomous navigation positioning means, and the display means, so that the radiation distribution of the measurement target site is obtained. A radiation distribution measurement system characterized by obtaining a figure. Provided with missing point extraction means for extracting missing points in the measurement target area,
The missing measurement point extraction means divides the measurement target area into a plurality of divided areas, associates each divided area with the radiation measurement value acquired in the divided area,
Further, the missing measurement location extracting means sets a divided region having the associated radiation measurement value as a measured region, a divided region without the associated radiation measurement value as an unmeasured region, and missing the unmeasured region. As a measurement point,
The radiation distribution measurement system according to claim 1, wherein the display unit displays the missing measurement part.   The missing measurement part extracting means sets the measured area associated with the radiation measurement value equal to or greater than a predetermined threshold as a caution area, and among the unmeasured areas, an unmeasured area having the caution area in the surroundings as a missing measurement area The radiation distribution measurement system according to claim 2, wherein:   The radiation distribution measurement system according to any one of claims 1 to 3, further comprising a glasses-type wearable terminal equipped with the position information acquisition unit, the autonomous navigation positioning unit, and the display unit.   The radiation distribution measurement system according to claim 4, wherein the display means of the glasses-type wearable terminal displays an augmented reality obtained by superimposing a real space and a radiation measurement value.

Images