Gamma radiation field simulation method, gamma radiation monitoring simulation training system and application

Abstract

The invention relates to a gamma radiation field simulation method, a gamma radiation monitoring simulation training system and application of the gamma radiation field simulation method and the gamma radiation monitoring simulation training system, and a three-dimensional simulation gamma radiation field and the gamma radiation monitoring simulation training system are constructed based on the Beidou positioning technology, the computer and communication technology and the action law of gamma rays and substances. The simulation training system is composed of a guide center, a Beidou positioning and communication base station, a simulation training ground, a simulation gamma radioactive source and a simulation gamma radiation monitor. The parts of the system exchange information through wired or wireless communication. The simulated gamma radiation source and the simulated gamma radiation monitor both have an accurate positioning function, and the simulated gamma radiation monitor also has a function of calculating and obtaining a gamma radiation dose rate and a dose. The problem of simulation and monitoring simulation training of a space gamma radiation field generated by a plurality of real gamma radioactive sources is solved, so that the effects of simulation training such as searching for more than one gamma radioactive source, determining gamma radioactive contamination boundaries and measuring personal accumulated doses are close to reality.

Description

Technical Field

[0001] The present invention belongs to the technical field of nuclear radiation monitoring, and in particular relates to a simulation method for a gamma radiation field, a gamma radiation monitoring simulation training system constructed based on the simulation method, and practical application of the simulation training system. Background Art

[0002] With the continuous development and widespread application of nuclear science and technology, the popularization of nuclear safety knowledge and the prevention and disposal of nuclear accidents have attracted great attention from the country.

[0003] After a nuclear accident occurs, the nuclear radiation environment is complex and diverse, including gamma radiation, neutron radiation, and alpha and beta radiation on the surface of objects. Timely monitoring of nuclear radiation intensity, defining the scope of nuclear contamination, and assessing the nature and level of nuclear contamination are the basic functions of the professional team for nuclear accident prevention and disposal.

[0004] Improving the knowledge level and professional skills of personnel in professional institutions for nuclear accident prevention and disposal, developing professional equipment, and strengthening the personal protection of professional team personnel have become the top priorities facing the national nuclear emergency management departments and professional teams.

[0005] Due to the hidden nature of nuclear radiation's harm to the human body and the country's strict control over nuclear radiation sources, there are the following problems if real radiation sources are used for nuclear radiation monitoring training. First, the radiation emitted by real radiation sources will cause radiation damage to trainees, causing great fear and seriously affecting the training effect. Second, the country strictly controls the purchase and sale of radiation sources, and the procedures for obtaining radiation sources are cumbersome and difficult. Third, once a radiation source is lost, it will cause harm to the public. If it is controlled and used by terrorists, it will cause nuclear terrorist accidents. For this reason, the country has extremely strict requirements for the management of radiation sources, and the legal responsibility for the safe storage of radiation sources is heavy.

[0006] Therefore, it is necessary to build a simulation training system for nuclear radiation monitoring, explore a set of methods to train and assess the professional skills of professional teams and their ability to deal with nuclear accidents on site without using real radiation sources, and design and equip the simulated radiation sources and simulated monitors required for simulation training.

[0007] Gamma radiation is the type of radiation that is most harmful to the human body under nuclear accident conditions. Therefore, it is imperative to simulate a space gamma radiation environment and build a simulation training system without using a real gamma radiation source. Summary of the invention

[0008] The purpose of the present invention is to propose a gamma radiation field simulation method, construct a gamma radiation monitoring simulation training system and its practical application, and train professional teams in gamma radiation monitoring skills without using real gamma radiation sources.

[0009] To achieve the above object, the technical solution of the gamma radiation field simulation method proposed in the present invention is: using Beidou RTK positioning technology and computer technology, a three-dimensional simulated gamma radiation field composed of a plurality of regular cubes is constructed on a training ground, in which each regular cube center point has a certain longitude, latitude and elevation, and the spatial position (longitude, latitude and elevation) of the center point of any cube A in the three-dimensional space is connected with the spatial position (longitude, latitude and elevation) of the center point of any cube B in the three-dimensional space. If the center point of cube A and the center point of cube B are at the same elevation, the plane distance X between the two center points can be calculated by substituting them into formula (1).

[0010]

[0011] Where:

[0012] X—the plane distance from the center point of cube A to the center point of cube B (m);

[0013] r—the average radius of the Earth, equal to 6.371×10 6 rice;

[0014] Φ1—the latitude of the center point of cube A;

[0015] Φ2—the latitude of the center point of cube B;

[0016] λ1—the longitude of the center point of cube A;

[0017] λ2—the longitude of the center point of cube B;

[0018] If the center point of cube A and the center point of cube B are not at the same elevation, substitute into formula (2) to calculate the spatial distance X between the two center points.

[0019]

[0020] Where:

[0021] X - the straight-line distance from the center of cube A to the center of cube B (m);

[0022] X′ – the distance between the orthographic projection point at the same elevation of the center point of cube A and the center point of cube B (m);

[0023] h – height difference between the center point of cube A and the center point of cube B (m);

[0024] Assuming that there is a simulated gamma radiation source with known nuclide and radioactivity located at the center of cube B, the simulated gamma radiation dose rate value at the center of cube A can be calculated by using formula (III):

[0025]

[0026] Where:

[0027] —Dose rate at a distance of x meters from the simulated gamma radiation source (Gy / h);

[0028] A—Simulated γ radiation source activity (Bq);

[0029] Γ—Air kerma rate constant (Gy.m 2 .Bq -1 .S -1 ), which can be obtained by looking up the table after the nuclide is determined;

[0030] μ—Linear attenuation coefficient of shielding material (such as air) (cm -1 ), this coefficient is related to the type of shielding material and the radiation energy generated by the radiation source, and can be obtained by looking up the table;

[0031] X—the spatial straight-line distance from the center point of cube A to the center point of cube B (m);

[0032] If n simulated γ radiation point sources with known nuclides and radioactivity are placed at different cube center points in three-dimensional space, the distances Xi (i=1, 2, ... n) between the center points of the n simulated γ radiation point sources and any cube center point P in the three-dimensional space (assuming that the simulated γ monitor is at the center point of the cube P) can be calculated by substituting them into formula (1) and formula (2) respectively, and then the simulated γ radiation dose rate value formed by each simulated γ radiation point source at the center point of the cube P can be obtained by substituting them into formula (3) respectively. Then, the dose rate generated by each simulated γ radiation source point source at the center of the cube P is accumulated and summed, and the total γ radiation dose rate value of n simulated γ radiation source point sources at the center of the cube P is obtained.

[0033] In the above-mentioned gamma radiation field simulation method and technical solution, the three-dimensional simulated gamma radiation field is based on precise Beidou RTK positioning technology, wireless communication technology and computer technology. On a training ground with specific terrain, a three-dimensional simulated gamma radiation field consisting of a number of cubes with a side length of 1 decimeter is constructed. The center point of each cube corresponds to each spatial position (longitude, latitude and elevation) positioned by Beidou RTK. The simulated gamma radiation source and the simulated gamma monitor located in the three-dimensional simulated gamma radiation field have their spatial positions determined by Beidou RTK positioning technology. When a spatial point position (longitude, latitude and elevation) of a simulated gamma radiation source falls into the three-dimensional simulated gamma radiation field, the simulated gamma radiation source and the simulated gamma monitor are located in the three-dimensional simulated gamma radiation field. In a certain cube, the center point (longitude, latitude and elevation) of the cube is regarded as the location of the simulated γ radiation source. Similarly, when a spatial point (longitude, latitude and elevation) of a simulated γ monitor falls into a certain cube of the three-dimensional simulated γ radiation field, the center point (longitude, latitude and elevation) of the cube is regarded as the location of the simulated γ monitor. Substitute the position information of the center point of cube A where the simulated γ monitor is located and the center point of cube B where the simulated γ radiation source is located into formula (I) and formula (II) to calculate the spatial distance X between the simulated γ radiation source and the simulated γ monitor, and then substitute it into formula (III) to calculate the simulated γ radiation dose rate value at the location of the simulated γ monitor. When n simulated gamma radiation sources are arranged in the three-dimensional simulated gamma radiation field, each simulated gamma radiation dose rate value is obtained by substituting them into the formula one by one. Then, the dose rates generated by n simulated gamma radiation sources at the location of the simulated gamma monitor are accumulated and summed to obtain the total gamma radiation dose rate at the location of the simulated gamma monitor.

[0034] To achieve the above-mentioned purpose, the present invention provides a technical solution of a γ radiation monitoring simulation training system, wherein the system comprises a γ radiation monitoring simulation training guidance center (hereinafter referred to as the guidance center), a positioning and communication base station, a γ radiation simulation training field (hereinafter referred to as the simulation training field), a simulated γ radiation source and a simulated γ monitor;

[0035] The guidance and control center includes a computer, a software module and a functional module; the software module includes a simulated γ radiation source and a simulated γ monitor working state detection and control module, a simulated γ radiation source setting module, a simulated γ radiation field calculation and evaluation module, a simulated training subject setting module, a trainee training assessment module, and a trainee and simulation equipment information management module; the functional module includes a face recognition module and a QR code recognition module;

[0036] The positioning and communication base station includes a Beidou RTK positioning reference station, a mobile wireless communication base station, and an optical fiber switch. The Beidou RTK positioning reference station and the mobile wireless communication base station are respectively connected to the optical fiber switch by optical signals or electrical signals;

[0037] The simulation training ground is a ground and space area with specific topography and a certain area that can meet the requirements of gamma radiation monitoring simulation training;

[0038] The simulated gamma radiation source is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, an acceleration sensor, a display module, an initial parameter storage module, a parameter selection manual button and a power supply. The mobile communication module, the Beidou RTK positioning module, the display module, the parameter storage module, and the parameter selection manual button are all electrically connected to the single-chip microcomputer, and the power supply provides electrical energy for the above components and the single-chip microcomputer;

[0039] The simulated γ monitor is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, a software module, an acceleration sensor, an alarm and display, an operation panel and a power supply. The software module includes a distance calculation module between a simulated γ radiation source and a simulated γ monitor, a γ dose rate calculation module, and a γ cumulative dose calculation module. The mobile communication module, the Beidou RTK positioning module, the acceleration sensor, the alarm and display, and the operation panel are all electrically connected to the single-chip microcomputer. The software module is pre-installed in the single-chip microcomputer. The power supply provides electrical energy for the above-mentioned components and the single-chip microcomputer. The appearance, shape, weight, alarm mode, response time and operation panel of the simulated γ monitor are the same as those of a real γ monitor.

[0040] The above-mentioned command and control center computer is connected to the optical fiber switch in the positioning and communication base station through an optical fiber or Ethernet cable in the form of optical signals or electrical signals. The Beidou RTK positioning module in the above-mentioned simulated γ radiation source and simulated γ monitor obtains positioning reference information from the Beidou RTK positioning base station. The wireless communication module in the above-mentioned simulated γ radiation source and simulated γ monitor maintains communication with the mobile wireless communication base station.

[0041] In the above-mentioned technical solution of the γ radiation monitoring simulation training system, the nuclide name and radioactivity intensity of the simulated γ radiation source can be manually set through the manual parameter selection button of the simulated γ radiation source, or can be preset by the computer of the command center and sent wirelessly to the simulated γ radiation source and stored in the initial parameter storage module.

[0042] In the above-mentioned technical solution of the γ radiation monitoring simulation training system, the power supply of the simulated γ radiation source has two states: standby and on. The power supply of the simulated γ radiation source can be turned on by a manual switch or remotely by a computer in the guidance and control center.

[0043] To achieve the above-mentioned purpose, the practical application technical solution of the γ radiation monitoring simulation training system provided by the present invention is:

[0044] First, build a γ radiation monitoring simulation training system:

[0045] The system comprises a γ radiation monitoring simulation training guidance center (hereinafter referred to as the guidance center), a positioning and communication base station, a γ radiation simulation training field (hereinafter referred to as the simulation training field), a simulated γ radiation source and a simulated γ monitor; the guidance center comprises a computer, a software module and a functional module; the software module comprises a simulated γ radiation source and a simulated γ monitor working state detection and control module, a simulated γ radiation source setting module, a simulated γ radiation field calculation evaluation module, a simulated training subject setting module, a trainee training assessment evaluation module, a trainee and simulation equipment information management module, and the functional module comprises a human face identification module and QR code identification module; the positioning and communication base station includes a Beidou RTK positioning base station, a wireless communication base station, and an optical fiber switch, and the Beidou RTK positioning base station and the wireless communication base station are respectively connected to the optical fiber switch by optical signals or electrical signals; the simulated training field is a ground and space area that can meet the requirements of γ radiation monitoring simulation training and has specific terrain and landforms and a determined area; the simulated γ radiation source is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, an acceleration sensor, a display module, an initial parameter storage module, a parameter selection manual button and a power supply, and the mobile communication The communication module, Beidou RTK positioning module, display module, parameter storage module, and parameter selection manual button are all electrically connected to the single-chip microcomputer, and the power supply provides power to the above-mentioned components and the single-chip microcomputer; the simulated γ monitor is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, a software module, an acceleration sensor, an alarm and display, an operation panel and a power supply. The software module includes a distance calculation module between the simulated γ radiation source and the simulated γ monitor, and a γ dose rate calculation module. The mobile communication module, Beidou RTK positioning module, acceleration sensor, alarm and display, and operation panel are all electrically connected to the single-chip microcomputer. The software module is pre-input into the single-chip microcomputer, the power supply provides power to the above-mentioned components and the single-chip microcomputer, the appearance, shape, weight, alarm mode, response time and operation panel of the simulated γ monitor are the same as those of the γ monitor actually in use; the above-mentioned guidance and control center computer is connected to the optical fiber switch in the positioning and communication base station through an optical fiber or Ethernet cable in the form of optical signals or electrical signals, the Beidou RTK positioning module in the above-mentioned simulated γ radiation source and the simulated γ monitor obtains positioning reference information from the Beidou RTK positioning base station, and the wireless communication module in the above-mentioned simulated γ radiation source and the simulated γ monitor maintains wireless communication with the wireless communication base station.

[0046] Second, build an outdoor γ radiation monitoring simulation training field:

[0047] Select an outdoor venue with specific terrain and area as a simulation training field, set up a Beidou RTK positioning base station and a wireless communication base station, and after the computer of the guidance and control center is powered on, the Beidou RTK positioning base station will transmit the Beidou positioning reference information obtained by the solution to the wireless communication base station through the optical fiber switch, and the wireless communication base station will broadcast the Beidou positioning reference information;

[0048] Third, simulate the layout and parameter setting of γ radiation source:

[0049] Each simulated gamma radiation source has a unique identity code (ID). When the simulated gamma radiation source is turned on and powered on, it is in a simulated radiation state.

[0050] One of the ways to arrange and set parameters of simulated gamma radiation sources: according to the requirements of simulated training, personnel arrange several simulated gamma radiation sources at different points in the simulated training field, and preset the nuclide name and radioactivity intensity through the manual button of each simulated gamma radiation source parameter selection. After the simulated gamma radiation source is powered on for self-test, the simulated gamma radiation source at each point performs joint calculation by receiving the positioning reference information of Beidou RTK and combining it with the Beidou information obtained by itself, and then sends its own ID code, Beidou precise positioning information and preset parameter information through the wireless communication module;

[0051] The second method of arranging and setting parameters of simulated gamma radiation sources is that when personnel arrange simulated gamma radiation sources at various points on the simulated training site and turn them on, the mobile communication module inside the simulated gamma radiation source in working state will jointly solve the received Beidou satellite signal and the received Beidou RTK base station signal, so that the simulated gamma radiation source can obtain centimeter-level positioning accuracy. Then, the simulated gamma radiation source automatically sends the precise positioning information (longitude, latitude and elevation) of its location to the mobile wireless communication base station through its wireless communication module, and then transmits it to the guidance and control center computer. After the guidance and control center receives the ID code of the simulated gamma radiation source at each point and the Beidou precise positioning information, it sets the nuclide type and radioactivity intensity of the simulated gamma radiation source at each point in the guidance and control center computer, and sends it to each simulated gamma radiation source, and stores it in the nuclide intensity storage module. Each simulated gamma radiation source then sends its own ID through the wireless communication base station. code, Beidou precise positioning and parameter information; in order to intuitively display the simulated training field and the simulated training effect, a simulated three-dimensional γ radiation field is constructed on the computer of the command and control center and displayed on the computer screen of the command and control center, and the simulated three-dimensional γ radiation field is divided into a number of 1 decimeter × 1 decimeter × 1 decimeter cubes. When the simulated γ radiation source is arranged in the simulated training field, the computer of the command and control center calculates the total simulated γ radiation dose rate data of each cube center point of the simulated three-dimensional γ radiation field according to the location of the simulated γ radiation source and the preset parameters using formula (I), formula (II) and formula (III), and stores the data in the electronic spreadsheet of the command and control center computer. When the location of the simulated γ monitor is in a certain cube space of the simulated three-dimensional γ radiation field, the computer of the command and control center can send the total simulated γ radiation dose rate data of the cube center point to the simulated γ monitor through wireless communication;

[0052] Fourth, simulated γ monitors enter the simulated training ground for practical training:

[0053] Each analog γ monitor has a unique identity code (ID). When the analog γ monitor is turned on and powered on, it is in the analog monitoring working state.

[0054] (1) Finding simulated γ radiation sources:

[0055] The mobile communication module of the simulated γ monitor in working state will receive the Beidou satellite signal and the Beidou RTK base station signal, and jointly calculate the centimeter-level positioning accuracy in real time. Then, the precise position information of the simulated γ radiation source in the working state and the precise position information of the simulated γ monitor itself will be substituted into formula (1) and formula (2) to calculate the distance X between the simulated γ monitor and the simulated γ radiation source, and then substitute it into formula (3) to calculate the γ radiation dose rate at a distance of X meters from the simulated γ radiation source. Substitute the other simulated γ radiation sources in the simulated training field into the above three formulas and calculate them one by one to obtain a set of γ radiation dose rates Finally, the total gamma radiation dose rate at the precise position of the simulated gamma monitor is obtained by accumulating and summing. The acceleration sensor in the simulated gamma monitor can sense the movement and stop status of the simulated gamma monitor. Each time it stops, a new position information is calculated and provided. When the simulated gamma monitor stops at a new position, the simulated gamma monitor will jointly solve its own Beidou positioning information and the received Beidou RTK positioning reference information again to obtain the precise positioning information of the new position, and then repeat the above calculation process to obtain the total gamma radiation dose rate at the new position.

[0056] When the simulated γ monitor continuously moves in the direction and route where the total γ radiation dose rate value increases, it indicates that the simulated γ monitor is gradually approaching a certain simulated γ radiation source. When a certain simulated γ radiation source is found, the precise position of the found simulated γ radiation source is reported to the guidance center by operating the power switch of the simulated γ monitor (pressing the power switch twice in quick succession). Subsequently, the power of the simulated γ radiation source is either turned off or all information of the found simulated γ radiation source is automatically shielded. When the simulated γ monitor continues to move in the direction and route where the total γ radiation dose rate value displayed on the simulated γ monitor gradually increases, the next simulated γ radiation source can be found until all simulated γ radiation sources are found.

[0057] (2) Determine the gamma radiation contamination area:

[0058] In the above scenario (1) of searching for a simulated gamma radiation source, when the total gamma radiation dose rate value observed by the trainee on the simulated gamma monitor reaches the safety critical value set for the simulated training subject, the trainee sends the precise location information of the simulated gamma monitor at that moment to the guidance center through the simulated gamma monitor (by pressing the power switch twice in quick succession) and makes a physical mark at that location (such as inserting a small red flag or dropping a tumbler device with positioning and sound and light alarm functions);

[0059] When the simulated γ monitor moves along the same direction and route as the total γ radiation dose rate value (safety critical value), and transmits the precise positioning information of each point that reaches the total γ radiation dose rate value (safety critical value) to the guidance and control center, on the computer screen of the guidance and control center, if these points with the same total γ radiation dose rate value (safety critical value) are connected into a line, the boundary line of the simulated radioactive contamination area measured on site by the trainees can be obtained; if the physical marks made by the trainees in the simulated training field are connected, the scope of the simulated γ radiation contamination area can be marked on site; the simulated radioactive contamination boundary line obtained by theoretical calculation of the guidance and control center and the boundary line measured in the training field can be compared, thereby assessing the training level of the trainees;

[0060] In the process of determining the simulated gamma radiation contamination area, the simulated gamma monitor can be carried by the trainees into the simulated training field to complete the entire simulated training process; the simulated gamma monitor can also be carried on a drone, which hovers and measures point by point at a certain height in the simulated training field, and then flies along the specified direction and route to complete the entire simulated training process; the simulated gamma monitor can also be carried on a ground robot, and the simulated gamma monitor is kept at a height of about 1 meter from the ground, measured point by point, and then moves along the specified direction and route to complete the entire simulated training process;

[0061] (3) Real-time monitoring of personal cumulative dose:

[0062] In the same scenario as (1) of finding a simulated gamma radiation source, a simulated gamma monitor is used to realize real-time measurement of personal cumulative dose. That is, the time from the start-up of the instrument or the completion of the previous total radiation dose rate measurement of the simulated gamma monitor to the completion of the current total radiation dose rate measurement is multiplied by the current total radiation dose rate to obtain the personal radiation dose received by the trainee in this gamma radiation measurement. The personal radiation dose received by the trainee in each gamma radiation measurement during the entire training process is added together to obtain the personal cumulative dose received by the trainee during this simulated training. When the personal cumulative dose reaches the threshold value that is harmful to the human body, the simulated gamma monitor can alarm. During the simulated training process, the simulated gamma monitor can also display the personal cumulative dose value in real time.

[0063] The advantages of the present invention are:

[0064] 1. The simulated gamma radiation field constructed by the present invention based on Beidou RTK positioning technology, computer technology and the attenuation law of gamma rays and air solves the simulation problem of the three-dimensional spatial distribution of multiple gamma radiation sources in the real gamma radiation field. Based on the simulated gamma radiation field provided by the present invention, the gamma radiation monitoring simulation training system can be simplified, low-cost and highly simulated, and can achieve the same training effect as using real gamma radiation sources.

[0065] 2. The positioning accuracy provided by the Beidou RTK positioning technology of the present invention is at the centimeter level, which is two to three orders of magnitude higher than the accuracy of directly using Beidou positioning. It solves the crucial problem of accurate positioning for simulating nuclear radiation monitoring, such as finding gamma radiation sources, determining radioactive contamination boundaries, and measuring personal cumulative doses, making simulation training simple, effective, and realistic.

[0066] 3. The present invention completes the top-level design of the γ radiation monitoring simulation training system. In addition to emitting the same communication signal as a mobile phone, the simulated γ radiation source does not have any traditional γ radiation source simulation materials such as magnetic lines and electromagnetic waves. Its radioactive intensity decay and the law of interaction with matter are exactly the same as those of a real γ radiation source, but it does not cause any harm to humans, meets green environmental protection requirements, and opens up a new path for simulation training of γ radiation monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a schematic diagram of the composition of the gamma radiation monitoring simulation training system of the present invention.

[0068] Figure 2 It is a schematic diagram of the composition of the simulated gamma radiation source of the present invention.

[0069] Figure 3 This is a schematic diagram of the composition of the simulated γ monitor of the present invention. (The two connecting lines have one-way arrows, which should be removed, that is, the connecting lines between the mobile communication module, Beidou RTK module and the single-chip microcomputer are bidirectional and do not need arrows)

[0070] Figure 4 This is a schematic diagram of a simulated gamma monitor and several simulated gamma radiation sources in a simulated training field in the first embodiment of the present invention.

[0071] Figure 5 It is a schematic diagram of the spatial distance between the calculation simulation gamma monitor and the simulated gamma radiation source of the present invention.

[0072] Figure 6 This is a schematic diagram comparing the measured results and theoretical calculation results of the simulation training of the γ-radioactive contaminated area of ​​the simulated nuclear radiation field in the second embodiment of the present invention.

[0073] Figure 7 This is a schematic diagram of the fifth embodiment of the present invention, which is a diagram of the aerial measurement of the gamma dose rate by a simulated gamma monitor carried by an unmanned aerial vehicle.

[0074] In the above figures, 1 is a nuclear radiation simulation training guidance center, 2 is a positioning and wireless communication base station, 3 is a nuclear radiation monitoring simulation training field, 4 is a simulated γ radiation source, 5 is a simulated γ monitor, 11 is a simulated equipment status detection and control module, 12 is a simulated radiation source setting module, 13 is a simulated nuclear radiation field calculation and evaluation module, 14 is a simulated training subject setting module, 15 is a training assessment module for trainees, 16 is a personnel and equipment information management module, 17 is a face and QR code recognition module, 18 is a computer, and 21 is a mobile wireless communication base station , 22 is a fiber optic switch, 23 is a Beidou RTK positioning base station, 41 is a Beidou RTK positioning module, 42 is a display module, 43 is a parameter selection manual button, 44 is a mobile wireless communication module, 45 is a single-chip microcomputer, 46 is a γ source parameter storage module, 47 is an acceleration sensor, 48 is a power supply, 51 is a Beidou RTK positioning module, 52 is an alarm and display module, 53 is an operation panel, 54 is a single-chip microcomputer, 55 is a mobile wireless communication module, 56 is an acceleration sensor, 57 is a power supply module, and 58 is a simulation γ detector software module; DETAILED DESCRIPTION

[0075] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0076] First, we need to build a nuclear radiation monitoring simulation training system. Figure 1 As shown, the system consists of a nuclear radiation monitoring simulation training guidance center (hereinafter referred to as the guidance center), a positioning and communication base station, a γ (nuclear) radiation simulation training field (hereinafter referred to as the simulation training field), a simulated γ radiation source and a simulated γ monitor.

[0077] 1. The guidance and dispatching center 1 is composed of a computer 18 and professional software modules. The computer 18 is used for data collection, processing, storage and display. The software modules are computing technology support modules, and the functions of each software module are as follows:

[0078] (1) The simulation instrument status detection and control software module 11 monitors the working status of all simulation instruments, including the simulation γ monitor, simulation γ radiation source, etc. When a simulation instrument fails, it gives a fault alarm message and controls the opening and closing of the simulation γ monitor or simulation γ radiation source.

[0079] (2) The simulated gamma radiation source setting software module 12 has the function of setting the nuclide name and intensity parameters of the simulated gamma radiation source.

[0080] (3) The simulation training field calculation and evaluation software module 13 has the function of establishing a simulated γ radiation field using a mathematical model according to the name and intensity of the nuclide;

[0081] (4) The simulation training subject setting software module 14 has the function of setting various training subjects according to needs, such as the search for simulated radiation sources, the measurement of the contamination boundary of simulated radiation sources, the measurement of personal cumulative dose, etc.

[0082] (5) The training assessment software module 15 for trainees has the function of assessing and evaluating the effectiveness of the simulated γ radiation monitoring training for trainees, including the assessment of the ability of individuals, teams, drones, and robots to find simulated γ radiation sources and determine the boundaries of simulated γ radiation contamination.

[0083] (6) Personnel and equipment information management module 16 has the function of managing the trainees and the simulated gamma radiation source and simulated gamma monitor, such as the maintenance and use records of the simulated gamma radiation source and simulated gamma monitor, technical indicators and training performance records of the trainees, etc.

[0084] (7) Face and QR code recognition management module 17 has the functions of face recognition and QR code recognition management. During training, it is necessary to bind the simulated γ monitor to the trainee for easy management. When the simulated γ monitor is used, after recognizing the trainee's face, the QR code of the simulated γ monitor held by the trainee is swiped, and the system binds the trainee to the simulated γ monitor. The γ radiation dose recorded by the instrument is recorded in the trainee's file until it is actively cancelled.

[0085] 2. The positioning and communication base station includes a Beidou RTK positioning base station 23, a mobile wireless communication base station 21 and a fiber optic switch 22. The fiber optic switch is a high-speed network transmission relay device.

[0086] (1) Beidou RTK positioning base station 23 includes Beidou positioning module and Beidou RTK module. RTK (Real-time kinematic) carrier phase differential technology is a differential method for real-time processing of carrier phase observations of two measurement stations. Beidou RTK base station must be a fixed station. It measures and calculates multiple satellite signals for a long time and a large number of times to minimize the errors caused by various factors in order to obtain its own accurate positioning. Beidou RTK positioning base station is used to provide positioning reference for simulated gamma radiation source and simulated gamma monitor. During simulation training, when the Beidou RTK positioning base station and the simulated gamma radiation source or simulated gamma monitor receive information sent by the same satellite at the same time, the Beidou RTK positioning base station can quickly solve the positioning error caused by these satellite information, and then broadcast the positioning error through the wireless communication base station. After the simulated gamma radiation source or simulated gamma monitor receives the positioning error sent by the Beidou RTK positioning base station, it transmits the Beidou positioning information and positioning error obtained by itself to its own RTK module for solution, thereby obtaining the precise positioning value of the simulated gamma radiation source or simulated gamma monitor, with a positioning accuracy of centimeters.

[0087] (2) The mobile communication base station 21 usually uses a mobile communication base station based on the 4G / 5G standard. Simulation training grounds in developed areas can use mobile 4G / 5G public network base stations. Accordingly, mobile public network communication modules must also be used in simulated γ monitors or simulated γ radiation sources. For nuclear radiation monitoring simulation training in remote areas such as deserts and Gobi, where mobile public network communication signals cannot reach, mobile private network communication base stations can be used. Accordingly, mobile private network communication modules must also be used in simulated γ radiation sources or simulated γ monitors.

[0088] 3. Simulate the gamma radiation source 4, as shown in the attached Figure 2 shown.

[0089] The simulated γ radiation source is composed of a Beidou RTK positioning module 41, a display module 42, a parameter selection manual button 43, a 4G / 5G public network (private network) communication module 44, a single-chip microcomputer 45, a γ source parameter storage module 46, an acceleration sensor 47, and a power supply 48. Each simulated γ radiation source has a unique identity code (ID). The initial parameters of the simulated γ radiation source, such as the name and intensity of the radioactive source nuclide, can be set remotely and wirelessly by a computer or manually through the parameter selection manual button 43. After the simulated γ radiation source nuclide name and intensity value are assigned, the intensity of the simulated γ radiation source obeys the exponential decay law, which is the same as the intensity decay law of the real γ radiation source.

[0090] 4. Analog gamma monitor 5, as attached Figure 3 shown.

[0091] The simulated γ monitor is composed of a Beidou RTK positioning module 51, an alarm and display 52, an operation panel 53, a single-chip microcomputer 54, a mobile wireless communication module 55, an acceleration sensor 56, a power supply 57 and a software module 58. The software module 58 includes a distance calculation module between the simulated radiation source and the simulated γ monitor, a γ dose rate calculation module and a γ cumulative dose calculation module.

[0092] The appearance, shape, alarm display method and operation method of the above-mentioned simulated γ monitor should be the same as the γ monitor of its actual model. In addition, in order for the simulated γ monitor to actively send data packets during simulation training, the simulated γ monitor is designed to have a dual-purpose power switch without changing the original appearance and operation method of the simulated γ monitor. The button needs to be pressed for more than 3 seconds to turn the power on and off. If the power switch is pressed twice quickly and the length of each time is no more than 1 second, the simulated γ monitor will send a data packet (such as positioning information, measurement data, etc.) to the guidance center. The guidance center receives and stores the data packets sent by the simulated γ monitor in real time, grasps the simulation training process, and assesses the simulation training results of the trainees. Example 1, Simulated γ radiation source search training:

[0093] During the development, use, storage and transportation of radioactive sources, accidents of lost radioactive sources occur from time to time. Quickly finding lost gamma radiation sources, alleviating public panic and reducing the hazards of nuclear radiation are important tasks that professional nuclear accident disposal teams often face.

[0094] The simulation of gamma radiation source search in this embodiment is carried out according to the following steps:

[0095] 1. Construction of simulation training ground:

[0096] Turn on all equipment such as the guidance and control center computer, positioning and mobile wireless communication base stations, and the positioning base station broadcasts the positioning reference information. According to the specified training area, the commander sets the coordinate system on the computer, and can also send the positioning information of several points on the boundary of the area, such as the four corners of a square, to the computer, and the computer automatically sets the training area coordinate system. In order to achieve the training effect, dozens to hundreds of simulated gamma radiation sources are usually placed in different positions of the training field, and several simulated gamma radiation sources are turned on as needed. This embodiment is set to work with ten simulated gamma radiation sources, and the power switches of ten of the simulated gamma radiation sources are turned on. It can be turned on manually by the guidance and control team members, or remotely by the guidance and control center computer. When the power of a simulated gamma radiation source is turned on, there is no feature, and the trainees cannot sense it, which is equivalent to hiding the location of the simulated gamma radiation source being sought. The simulated gamma radiation source in working state obtains the reference positioning information provided by the Beidou RTK positioning base station through the mobile wireless communication base station broadcast, and then retrieves its own Beidou positioning information, and sends these two information to the Beidou RTK positioning module of the simulated gamma radiation source for solution to obtain its own accurate positioning. Then the simulated gamma radiation source automatically transmits its accurate positioning (longitude, latitude and altitude) and ID code information to the guidance and control center computer through the mobile wireless communication base station. All simulated gamma radiation sources are laid out. At this point, the layout and positioning of simulated gamma radiation sources are completed, and the construction of the gamma (nuclear) radiation simulation training field is completed.

[0097] 2. Preset and broadcast the parameters of the simulated gamma radiation source:

[0098] According to the training requirements, the commander clicks on the simulated γ radiation source parameter setting page on the computer screen to set the nuclide names (such as cobalt-60, cesium-137, etc.) and the intensity of each simulated γ radiation source (such as 10 Curies, 100 Curies, etc.) of ten simulated γ radiation sources (n=10). Each simulated γ radiation source with an ID number can be set with one or more nuclides, and each nuclide can be set with an intensity. For example, if the nuclides of simulated γ radiation source No. 1 are cobalt-60 and cesium-137, the intensity of cobalt-60 is 10 Curies, and the intensity of cesium-137 is 20 Curies, and the nuclides of simulated γ radiation source No. 2 are iridium-192, and the intensity is 30 Curies, the nuclides and intensities of all simulated γ radiation sources are set. At this time, the computer screen will display the position, working status and set parameters of each simulated γ radiation source in the simulated training field. Immediately, the command and control center broadcasts the position and parameter information of all simulated γ radiation sources through mobile wireless communication base stations. At this point, the parameters of the simulated γ radiation source have been preset.

[0099] The distribution of simulated gamma radiation sources is usually fixed when they are arranged. If it is necessary to change the distribution of simulated gamma radiation sources, it can be achieved by turning off the power of one or some simulated gamma radiation sources or setting the intensity value of the simulated gamma radiation source to zero.

[0100] 3. Simulate the gamma monitor to enter the training ground:

[0101] Participants hold simulated γ monitors and enter the simulated training field. Figure 4 As shown in the figure, the simulated γ monitor enters the working state after the power-on self-test. The simulated γ monitor obtains the positioning reference information through the mobile wireless communication base station. After receiving the positioning reference information, the simulated γ monitor retrieves its own Beidou information and sends the two information to the Beidou RTK positioning module of the simulated γ monitor for solution to obtain the accurate positioning information of the simulated γ monitor itself, store it and send it to the computer of the guidance and control center. The accurate position of the simulated γ radiation source and the simulated γ monitor is displayed on the computer screen of the guidance and control center. Acceleration sensors are designed in the simulated γ monitor and the simulated γ radiation source to detect the movement of the simulated γ monitor and the simulated γ radiation source. They are only allowed to send information once each time they move. This design controls the frequent sending of data information, avoids the congestion of the guidance and control center due to receiving massive data when the number of simulated γ monitors and simulated γ radiation sources is large, and also saves electricity.

[0102] 4. Find simulated gamma radiation source:

[0103] At the beginning of the search, the simulated γ monitor sends a request message through the mobile wireless communication base station to obtain the location, nuclide, intensity and ID code information of the ten simulated γ radiation sources. Considering the different altitudes of the ten simulated γ radiation sources (due to topography), two calculation methods of the distance X are given. When the simulated γ monitor and the simulated γ radiation source are at the same altitude, the calculation result of formula (I) is the distance between the simulated γ radiation source and the simulated γ monitor.

[0104]

[0105] Where:

[0106] X—the distance between the simulated γ monitor’s orthographic projection position and the simulated γ radiation source at the same elevation (m);

[0107] r—the average radius of the Earth, equal to 6.371×10 6 rice;

[0108] Φ1—latitude of the simulated γ monitor;

[0109] Φ2—latitude of simulated γ radiation source;

[0110] λ1—Longitude of the simulated γ monitor;

[0111] λ2—the longitude of the simulated gamma radiation source;

[0112] When the simulated γ monitor and the simulated γ radiation source are at different altitudes, as shown in the attached Figure 5As shown, the position (Φ1, λ1, h1) of the simulated γ monitor 5 is first projected to the elevation of a simulated γ radiation source 4 (Φ2, λ2, h2) to form an orthographic projection point 5′ (Φ1′, λ1′, h2). Substituting it into formula (1) is calculated to obtain X′, where X′ is the straight-line distance between the orthographic projection position of the simulated γ monitor 5 and the simulated γ radiation source 4 at the same elevation. X′ is one right-angled side of the right triangle, and the difference in elevation between the simulated γ monitor 5 and the simulated γ radiation source 4 (h=|h1-h2|) is the other right-angled side of the right triangle. The spatial distance X between the simulated γ monitor 5 and the simulated γ radiation source 4 can be calculated by the Pythagorean theorem.

[0113]

[0114] Where:

[0115] X - the distance from the simulated γ monitor to the simulated γ radiation source (m);

[0116] X′ - the distance from the orthographic projection point of the simulated γ monitor to the simulated γ radiation source at the same height (m);

[0117] h – the elevation difference between the simulated γ monitor and the simulated γ radiation source (m).

[0118] According to the above method, the spatial distance X1-X10 between the location of the simulated γ monitor and the locations of ten simulated γ radiation sources at different altitudes can be calculated.

[0119] Substitute X1-X10 into formula (III) to obtain the gamma radiation dose rate generated by each simulated gamma radiation source in the simulated gamma monitor.

[0120]

[0121] Where:

[0122] —Dose rate at X meters from the simulated gamma radiation source (Gy / h);

[0123] A—Simulated γ radiation source activity (Bq);

[0124] Γ—Air kerma rate constant (Gy.m2.Bq -1 .S -1 ), which can be obtained by looking up the table after the nuclide is determined;

[0125] μ—Linear attenuation coefficient of shielding material (such as air) (cm -1 ), this coefficient is related to the type of shielding material and the radiation energy generated by the radiation source, and can be obtained by looking up the table;

[0126] X—the spatial straight-line distance from the center point of cube A to the center point of cube B (m);

[0127] Finally, the gamma radiation dose rates generated by the ten simulated gamma radiation sources are summed to obtain the total gamma radiation dose rate at the location of the simulated gamma monitor.

[0128] When the simulated γ monitor moves to a new point, the simulated γ monitor will substitute its own new point position information and the simulated γ radiation source position and parameter information into formula (I) and formula (II) again to calculate the spatial distance X of the new point, and then substitute X into formula (III) to calculate the γ radiation dose rate of the new point of the simulated γ monitor, and sum to obtain the total γ radiation dose rate of the new point. It can be seen from formula (III) that the smaller the distance X, the greater the γ radiation dose rate. When the simulated γ monitor moves along the direction of increasing total γ radiation dose rate, it means that the simulated γ monitor is getting closer to a simulated γ radiation source with a larger radioactive intensity until the simulated γ radiation source is found. At this moment, the trainee operates the switch of the simulated γ monitor (press the power switch twice in quick succession) to send the precise position, ID code and measurement data packet of the simulated γ monitor to the guidance center. In order to eliminate the influence of the simulated γ radiation source that has been found on the simulated γ monitor, the trainee should manually turn off the power of the simulated γ radiation source that has been found. Next, the simulated gamma monitor continues to search for the remaining simulated gamma radiation sources according to the above method steps until all the arranged simulated gamma radiation sources are found;

[0129] If more than one simulated gamma monitor is used for training at the same time, each simulated gamma monitor can complete the above positioning and calculation process independently, thus shortening the time spent on finding all simulated gamma radiation sources. Trainees or teams that find reasonable routes and take short time can get high scores.

[0130] It should be noted that each time the total gamma radiation dose rate is measured, the simulated gamma monitor must obtain the positioning information of the simulated gamma radiation source and itself, and then calculate the spatial straight-line distance between the simulated gamma monitor and the simulated gamma radiation source, and then calculate the gamma radiation dose rate and the total gamma radiation dose rate. When the real instrument measures the gamma radiation dose rate, it needs to stay for 1 second to several seconds, which is called the reading establishment time. The time it takes for a simulated gamma monitor to measure a total gamma radiation dose rate (positioning and total radiation dose rate calculation time) should be the same as the reading establishment time of a gamma radiation monitor of the same model.

[0131] The location of each measurement point of the simulated γ monitor, the total γ radiation dose rate data and ID obtained by the measurement can be sent automatically by the simulated γ monitor or manually by the trainees to the computer of the guidance center. The computer can display the trainee's path and total γ radiation dose rate information in real time, and can also display the time taken by the trainee to find the simulated γ radiation source. The shorter the path and the shorter the time, the better the measurement method, which is the basic principle of automatic evaluation of radiation source search simulation training.

[0132] The nuclide and radioactivity intensity of the simulated gamma radiation source can be set by the guidance and control center or manually preset by selecting the parameter manual button 43. Figure 2 The location information and parameter information of this simulated γ radiation source can be directly acquired by the simulated γ monitor through the mobile wireless communication base station, thereby completing the monitoring of the γ radiation dose rate and further completing the task of finding the simulated γ radiation source.

[0133] Example 2: Training on the definition of the γ-radioactive contaminated area in a nuclear radiation field simulation:

[0134] After a nuclear accident occurs, gamma rays are the most harmful to the human body. According to the gamma ray dose rate, the area where the nuclear accident occurred is usually divided into severe nuclear radiation contamination areas and general nuclear radiation contamination areas. Personnel and equipment are prohibited from entering the severe nuclear radiation contamination area. The basis for dividing the boundary line between the severe nuclear radiation contamination area and the general nuclear radiation contamination area is whether the gamma radiation dose rate reaches the safety critical value. If the many points in the simulated gamma radioactive contamination area that reach the safety critical value are connected into a line, it is the boundary line of the simulated severe nuclear radiation contamination area. The area surrounded by the boundary line is the simulated severe nuclear radiation contamination area.

[0135] The construction of the simulated training ground in the second embodiment is the same as that in the first embodiment.

[0136] The simulation training methods of the second embodiment can be divided into two types.

[0137] The first simulation training method is that the simulated γ radiation source arranged in the simulation training field is manually preset with nuclides and intensity through the parameter selection manual button. The intensity of the simulated γ radiation source obeys the exponential decay law, which is the same as the intensity decay law of the real radiation source. After the simulated γ radiation source is turned on, its position information and parameter information are broadcasted through the wireless communication base station.

[0138] Several trainees in the same team held simulated γ monitors and stood around the simulated nuclear radiation training ground according to instructions. The commander gave the safety critical value of the total γ radiation dose rate and instructed the measurement training to begin. The trainees held the simulated γ monitors, adjusted their positions and directions, and quickly measured to find the points where the total γ radiation dose rate was the safety critical value. Every time a point where the total γ radiation dose rate was the safety critical value (within the specified relative error range) was measured, the power switch of the simulated γ monitor was manually triggered twice quickly, and the data packet consisting of the location information, ID code, and measurement value of the point where the simulated γ monitor was located was sent to the guidance and dispatching center computer through the mobile wireless communication base station. The guidance and dispatching center computer received and stored the data packet and displayed it on its screen. After each measurement, the team trainees quickly sent a data packet consisting of the location information, ID code, and measurement value to the guidance and dispatching center computer, and also made physical marks on the ground of the simulated training ground (such as inserting a warning red flag or placing a tumbler device with sound and light alarm and positioning functions). After the team members complete the specified number of measurements in the specified area, they can connect the points with the same total gamma radiation dose rate value into a line on the computer screen of the guidance center to display the boundary line of the simulated radioactive contamination area measured on site. If the physical marks made on the simulation training field are connected into a line (warning line), the scope of the simulated radioactive contamination area is marked.

[0139] The relative error between each measurement data of the trainees and the given safety critical dose rate value should be within the specified range (for example, ±20%). If it exceeds this range, it will be regarded as not meeting the requirements and the corresponding score will be deducted during the assessment. During the assessment, it is necessary to consider not only the time for all trainees in the team to complete the measurement, but also the total absolute value of the error of each member's measurement each time, and comprehensively evaluate the results.

[0140] It should be noted that the time required for a simulated gamma monitor to measure the total gamma radiation dose rate produced by multiple simulated gamma radiation sources should be close to the measurement (reading establishment) time of an actual model of nuclear radiation monitoring instrument.

[0141] The advantage of this simulation training method is that the simulated gamma monitor directly obtains the position and parameter information of the simulated gamma radiation source, and there is no need for the guidance center computer to set the simulated gamma radiation source parameters in advance, nor is there any need for the guidance center computer to perform theoretical calculations on the relevant data of the simulated training field.

[0142] The second method of simulation training in the second embodiment is that the guidance and control center presets the simulated gamma radiation source parameters, calculates and establishes the coordinate system and the simulated space radiation field, and sends the corresponding gamma dose rate data as the measurement data of the simulated gamma monitor according to the three-dimensional position information provided by the simulated gamma monitor.

[0143] Step 1: Build a simulation training ground:

[0144] In order to adapt to the simulated measurement of personnel on foot and drones, the simulation training ground is set as a three-dimensional cube of 100 meters × 100 meters × 100 meters, and the simulation training ground is divided into 10 9 A cube of 1 dm x 1 dm x 1 dm is formed, and the center point of each cube is used as the characteristic point of the cube. In this way, the spatial point position (longitude, latitude and elevation) of each simulated γ radiation source arranged in the simulation training field falls into a cube of the three-dimensional simulation training field, and the center point (longitude, latitude and elevation) of the cube is regarded as the location of the simulated γ radiation source. Similarly, when the spatial point position (longitude, latitude and elevation) of each simulated γ monitor (carried by personnel, drones or robots) entering the simulation training field falls into a cube of the three-dimensional simulation training field, the center point (longitude, latitude and elevation) of the cube is regarded as the location of the simulated γ monitor.

[0145] Step 2: Establish a simulated γ radiation field:

[0146] When the simulated gamma radiation sources are arranged in the simulated training field, the guidance center computer uses formula (1) and formula (2) to calculate the spatial distance between each simulated gamma radiation source and each cube center point (feature point) in the three-dimensional simulated training field according to the number, location, nuclide and intensity of the simulated gamma radiation sources, and calculates the gamma radiation dose rate of each cube center point according to formula (3). The total gamma radiation dose rate of each cube center point in the three-dimensional simulated training field is obtained by accumulating and summing. 9 The total gamma radiation dose rate data of the center points of the cube is generated into a spreadsheet and stored in the computer of the control center for quick query.

[0147] The third step is to simulate the gamma radiation dose rate measurement:

[0148] The trainees enter the simulation training ground holding a simulated γ monitor and start the self-test. First, the simulated γ monitor obtains the Beidou RTK benchmark positioning data through the mobile wireless communication base station, and then obtains its own Beidou positioning information, which is sent to its own Beidou RTK module for joint solution to obtain the precise positioning information of the simulated γ monitor itself, and then sent to the guidance and control center through wireless communication. The guidance and control center computer determines the cube position of the simulated γ monitor in the three-dimensional simulation training ground based on the precise positioning information transmitted by the simulated γ monitor, and obtains the simulated total γ radiation dose rate data corresponding to the center point of the cube position by looking up the table, and sends it to the simulated γ monitor through the mobile wireless communication base station. After the simulated γ monitor receives the total γ radiation dose rate data information, it sends it to the display for display, and if the value exceeds the alarm threshold, an alarm sound is issued.

[0149] This simulation training method is to construct a three-dimensional simulation training field on the computer of the command and control center, which can intuitively display the positions of the simulated γ radiation source and the simulated γ monitor in the simulation training field on the computer screen of the command and control center. The parameter values ​​(such as nuclide, radioactivity intensity) set by the command and control center for each simulated γ radiation source can also be displayed on the computer screen.

[0150] When the trainees enter the simulation training ground holding a simulation monitor, each time they stop at a measuring point and send the position information, the computer of the guidance center will look up the table, send the total radiation dose rate data corresponding to the point to the simulation monitor and display it. Once the total gamma radiation dose rate of the simulated gamma monitor reaches the safety critical value (within the specified error range), the trainees will send the location, ID code and displayed gamma radiation dose rate value of the simulated gamma monitor to the computer of the guidance center, which will record and display it.

[0151] If the coordinate points with the same total gamma radiation dose rate (meeting the error requirement) at a height of 1 meter relative to the ground are connected into a line on the computer screen of the guidance and control center, the theoretical calculated boundary line of the simulated radioactive contamination area with a safety critical value is formed, as shown in the attached figure. Figure 6 Medium 计算 Indicated by solid boundary.

[0152] The simulated radioactive contaminated area boundary line P calculated by the guidance center computer 计算 The simulated radioactive contaminated area boundary line P measured on site by the trainees 实测 For comparison, see Appendix Figure 6 , the simulation training results can be judged.

[0153] The disadvantage of the second method of simulation training in the second embodiment is that the simulated γ monitor needs to continuously send positioning information to the guidance center to obtain the total γ radiation dose rate value of the new point. Every time a point with a total γ radiation dose rate of a safe boundary value is measured, it needs to communicate with the guidance center computer multiple times, and the power consumption of the simulated γ monitor will become relatively large. When many simulated γ monitors continuously send information to the computer, the computer needs to have a very high performance to quickly process the massive information.

[0154] In the two simulation training methods given in the second embodiment, the simulated γ monitor can also be mounted on a ground walking robot. The simulated γ monitor is 1 meter above the ground and is remotely controlled by the trainees.

[0155] Example 3: Aerial survey training of a simulated γ-ray monitor carried by a drone:

[0156] The first step is to build a simulation training ground:

[0157] According to the second simulation training method in Example 2, a 100m×100m×100m three-dimensional cube-shaped nuclear radiation monitoring simulation training field is established, and all equipment such as the guidance and control center computer, positioning and mobile wireless communication base station are turned on, and the positioning reference station broadcasts the positioning reference information to the outside. The coordinate system of the drone detection area is set on the computer according to the specified simulation training area.

[0158] The second step is to construct the γ simulation radiation field:

[0159] 1-n simulated gamma radiation sources are arranged at different locations of the simulated training ground (with different longitude, latitude and altitude), and the power switches of several of them are turned on. The simulated gamma radiation sources in working state obtain the reference positioning information of the Beidou RTK positioning base station through the mobile wireless communication base station broadcast, and the computer of the command and control center presets the nuclide and intensity parameters for each simulated gamma radiation source.

[0160] The third step is to simulate aerial survey training:

[0161] The simulated gamma monitor carried by the drone entered the simulated nuclear radiation contaminated area. Figure 7 As shown, according to the planned altitude and path, point-by-point hovering measurements are performed over the nuclear radiation simulation training ground.

[0162] The unmanned aerial vehicle simulated γ monitor sends request information through a mobile wireless communication base station to obtain and store the ID, positioning longitude, latitude and altitude information (Φi, λi, hi, i=1,2,...n), nuclide and source strength information of each simulated γ radiation source. Since the location of the simulated γ monitor on the unmanned aerial vehicle is different from the location of the simulated γ radiation source, the aerial location of the simulated γ monitor on the unmanned aerial vehicle should be projected to the same elevation of each simulated γ radiation source to form the longitude, latitude and elevation information of the projection point (Φp1, λp1, hi), and then the longitude, latitude and elevation information of the simulated γ radiation source point are substituted into formula (I) to obtain the distance X11-Xnn (meters) between the orthographic projection point of the unmanned aerial vehicle simulated γ monitor and the simulated γ radiation source point at the same elevation. Then, X11-Xnn and the elevation difference h (the relative height between the location of the simulated γ monitor on the unmanned aerial vehicle and its orthographic projection point) are substituted into formula (II) to obtain the spatial distance X1-Xn between the simulated γ monitor on the unmanned aerial vehicle and the simulated γ radiation source and store it.

[0163] Substitute X1-Xn into formula (III) to obtain the gamma radiation dose rate generated by the simulated gamma radiation source 1-n at the location of the simulated gamma monitor on the drone, and finally sum up to obtain the total gamma radiation dose rate, which is then transmitted to the guidance and control center via wireless. The measurement is now complete. The drone flies to the next or more locations and continues the above steps to complete the gamma radiation dose rate measurement of the next or more locations. The measurement process should take the same time as the measurement (reading establishment) time of the actual aerial survey instrument.

[0164] In the above calculation process, if the height of the hovering point of the simulated γ monitor on the unmanned aerial vehicle is lowered to a height of 1 meter from the ground, and then the positioning information at the point 1 meter from the ground is substituted into formula (2) and formula (3) to calculate the total γ radiation dose rate, when the points where the calculated total γ radiation dose rate reaches the safety critical value are connected, the boundary line of the nuclear radiation contaminated area on the ground of the simulated training ground can be obtained.

[0165] Example 4: Real-time measurement simulation training of personal gamma radiation cumulative dose:

[0166] Under the scenario of searching for a simulated gamma radiation source given in the first embodiment, a simulated gamma monitor is used to achieve real-time measurement of personal gamma cumulative dose.

[0167] When the trainees enter the simulation training ground holding a simulated gamma monitor, the time from the time the instrument is turned on or the time from the completion of the previous radiation dose rate measurement to the completion of the current radiation dose rate measurement is multiplied by the current radiation dose rate to obtain the personal radiation dose received by the trainees in this gamma radiation measurement. The personal radiation dose received in each gamma radiation measurement during the entire training process is added together to obtain the personal cumulative dose received by the trainees during this simulation training. When the personal cumulative dose reaches the threshold that is harmful to the human body, the simulated gamma monitor can alarm. During the simulation training, the simulated gamma monitor can also display the personal cumulative dose value in real time.

Claims

1. A method for simulating a gamma radiation field, characterized in that: Using Beidou RTK positioning technology and computer technology, a three-dimensional simulated γ radiation field consisting of several regular cubes is constructed on the training ground. In the three-dimensional simulated γ radiation field, each regular cube center point has a certain longitude, latitude and elevation. The spatial position (longitude, latitude and elevation) of the center point of any cube A in the three-dimensional space is connected with the spatial position (longitude, latitude and elevation) of the center point of any cube B in the three-dimensional space. If the center point of cube A and the center point of cube B are at the same elevation, the plane distance X between the two center points can be calculated by substituting them into formula (1). Where: X—the plane distance from the center point of cube A to the center point of cube B (m); r—the average radius of the Earth, equal to 6.371×10 6 rice; Φ1—the latitude of the center point of cube A; Φ2—the latitude of the center point of cube B; λ1—the longitude of the center point of cube A; λ2—the longitude of the center point of cube B; If the center point of cube A and the center point of cube B are not at the same elevation, substitute into formula (2) to calculate the spatial distance X between the two center points. Where: X - the straight-line distance from the center of cube A to the center of cube B (m); X′ – the distance between the orthographic projection point at the same elevation of the center point of cube A and the center point of cube B (m); h – height difference between the center point of cube A and the center point of cube B (m); Assuming that there is a simulated γ radiation source with known nuclide and radioactivity located at the center of cube B, the simulated γ radiation dose rate value at the center of cube A can be calculated by using formula (III): Where: —Dose rate at a distance of X meters from the simulated gamma radiation source (Gy / h); A—Simulated γ radiation source activity (Bq); Γ—Air kerma rate constant (Gy.m 2 .Bq -1 .S -1 ), after the nuclide is determined, it can be obtained by looking up the table; μ—Linear attenuation coefficient of shielding material (such as air) (cm -1 ), this coefficient is related to the type of shielding material and the radiation energy generated by the radiation source, and can be obtained by looking up the table; X—the spatial straight-line distance from the center point of cube A to the center point of cube B (m); If n simulated γ radiation point sources with known nuclides and radioactivity are placed at different cube center points in three-dimensional space, the distances Xi (i=1, 2, ... n) between the center points of the n simulated γ radiation point sources and any cube center point P in the three-dimensional space (assuming that the simulated γ monitor is at the center point of the cube P) can be calculated by substituting them into formula (1) and formula (2) respectively, and then the simulated γ radiation dose rate value formed by each simulated γ radiation point source at the center point of the cube P can be obtained by substituting them into formula (3) respectively. Then, the dose rate generated by each simulated γ radiation source point source at the center point of the cube P is accumulated and summed, and the total γ radiation dose rate value of n simulated γ radiation source point sources at the center point of the cube P is obtained.

2. A gamma radiation field simulation method according to claim 1, characterized in that: The three-dimensional simulated γ radiation field is based on precise Beidou RTK positioning technology, wireless communication technology and computer technology. On a training ground with specific topography, a three-dimensional simulated γ radiation field consisting of a number of cubes with a side length of 1 decimeter is constructed. The center point of each cube corresponds to each spatial position (longitude, latitude and elevation) positioned by Beidou RTK. The simulated γ radiation source and the simulated γ monitor located in the three-dimensional simulated γ radiation field have their spatial positions determined by Beidou RTK positioning technology. When a spatial point position (longitude, latitude and elevation) of a simulated γ radiation source falls into a cube of the three-dimensional simulated γ radiation field, the center point of the cube corresponds to each spatial position (longitude, latitude and elevation) positioned by Beidou RTK. The center point of the cube (longitude, latitude and elevation) is regarded as the location of the simulated γ radiation source. Similarly, when a spatial point (longitude, latitude and elevation) of a simulated γ monitor falls into a cube of the three-dimensional simulated γ radiation field, the center point (longitude, latitude and elevation) of the cube is regarded as the location of the simulated γ monitor. Substitute the position information of the center point of cube A where the simulated γ monitor is located and the center point of cube B where the simulated γ radiation source is located into formula (1) and formula (2) to calculate the spatial distance X between the simulated γ radiation source and the simulated γ monitor, and then substitute it into formula (3) to calculate the simulated γ radiation dose rate value at the location of the simulated γ monitor. When n simulated gamma radiation sources are arranged in the three-dimensional simulated gamma radiation field, each simulated gamma radiation dose rate value is obtained by substituting them into the formula one by one. Then, the dose rates generated by n simulated gamma radiation sources at the location of the simulated gamma monitor are accumulated and summed to obtain the total gamma radiation dose rate at the location of the simulated gamma monitor.

3. A gamma radiation monitoring simulation training system, characterized in that: The system consists of a gamma radiation monitoring simulation training guidance center (hereinafter referred to as the guidance center), a positioning and communication base station, a gamma (nuclear) radiation simulation training field (hereinafter referred to as the simulation training field), a simulated gamma radiation source and a simulated gamma monitor; The guidance and adjustment center includes a computer, a software module and a functional module; the software module includes a simulated γ radiation source and a simulated γ monitor working state detection and control module, a simulated γ radiation source setting module, a simulated γ radiation field calculation evaluation module, a simulated training subject setting module, a trainee training assessment module, and a trainee and simulation equipment information management module; the functional module includes a face recognition module and a QR code recognition module; The positioning and communication base station includes a Beidou RTK positioning reference station, a mobile wireless communication base station, and an optical fiber switch. The Beidou RTK positioning reference station and the mobile wireless communication base station are respectively connected to the optical fiber switch by optical signals or electrical signals; The simulation training ground is a ground and space area with specific topography and a certain area that can meet the requirements of gamma radiation monitoring simulation training; The simulated gamma radiation source is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, an acceleration sensor, a display module, an initial parameter storage module, a parameter selection manual button and a power supply. The mobile communication module, the Beidou RTK positioning module, the display module, the parameter storage module, and the parameter selection manual button are all electrically connected to the single-chip microcomputer, and the power supply provides electrical energy for the above components and the single-chip microcomputer; The simulated γ monitor is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, a software module, an acceleration sensor, an alarm and display, an operation panel and a power supply. The software module includes a distance calculation module between a simulated γ radiation source and the simulated γ monitor and a γ dose rate calculation module. The mobile communication module, the Beidou RTK positioning module, the acceleration sensor, the alarm and display, and the operation panel are all electrically connected to the single-chip microcomputer. The software module is pre-installed in the single-chip microcomputer. The power supply provides electrical energy for the above components and the single-chip microcomputer. The appearance, shape, weight, alarm mode, response time and operation panel of the simulated γ monitor are the same as those of the real γ monitor. The above-mentioned command and control center computer is connected to the optical fiber switch in the positioning and communication base station through an optical fiber or Ethernet cable in the form of optical signals or electrical signals. The Beidou RTK positioning module in the above-mentioned simulated γ radiation source and simulated γ monitor obtains positioning reference information from the Beidou RTK positioning base station. The wireless communication module in the above-mentioned simulated γ radiation source and simulated γ monitor maintains communication with the mobile wireless communication base station.

4. A gamma radiation monitoring simulation training system according to claim 3, characterized in that: The nuclide name and radioactivity intensity of the simulated γ radiation source can be manually set through the parameter selection manual button of the simulated γ radiation source, or preset by the computer of the control center and sent to the simulated γ radiation source wirelessly and stored in the initial parameter storage module.

5. A gamma radiation monitoring simulation training system according to claim 3, characterized in that: The power supply of the simulated gamma radiation source has two states: standby and on. The power supply of the simulated gamma radiation source can be turned on by a manual switch or remotely by a computer at a control center.

6. A practical application of a γ radiation monitoring simulation training system, characterized by: First, build a γ radiation monitoring simulation training system: The system comprises a γ radiation monitoring simulation training guidance center (hereinafter referred to as the guidance center), a positioning and communication base station, a γ radiation simulation training field (hereinafter referred to as the simulation training field), a simulated γ radiation source and a simulated γ monitor; the guidance center comprises a computer, a software module and a functional module; the software module comprises a simulated γ radiation source and a simulated γ monitor working state detection and control module, a simulated γ radiation source setting module, a simulated γ radiation field calculation evaluation module, a simulated training subject setting module, a trainee training assessment evaluation module, a trainee and simulation equipment information management module, and the functional module comprises a human face identification module and QR code identification module; the positioning and communication base station includes a Beidou RTK positioning base station, a wireless communication base station, and an optical fiber switch, and the Beidou RTK positioning base station and the wireless communication base station are respectively connected to the optical fiber switch by optical signals or electrical signals; the simulated training field is a ground and space area that can meet the requirements of γ radiation monitoring simulation training and has specific terrain and landforms and a determined area; the simulated γ radiation source is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, an acceleration sensor, a display module, an initial parameter storage module, a parameter selection manual button and a power supply, and the mobile communication The communication module, Beidou RTK positioning module, display module, parameter storage module, and parameter selection manual button are all electrically connected to the single-chip microcomputer, and the power supply provides power to the above-mentioned components and the single-chip microcomputer; the simulated γ monitor is composed of a mobile communication module, a Beidou RTK positioning module, a single-chip microcomputer, a software module, an acceleration sensor, an alarm and display, an operation panel and a power supply. The software module includes a distance calculation module between the simulated γ radiation source and the simulated γ monitor, and a γ dose rate calculation module. The mobile communication module, Beidou RTK positioning module, acceleration sensor, alarm and display, and operation panel are all electrically connected to the single-chip microcomputer. The software module is pre-input into the single-chip microcomputer, the power supply provides power to the above-mentioned components and the single-chip microcomputer, the appearance, shape, weight, alarm mode, response time and operation panel of the simulated γ monitor are the same as those of the γ monitor actually in use; the above-mentioned guidance and control center computer is connected to the optical fiber switch in the positioning and communication base station through an optical fiber or Ethernet cable in the form of optical signals or electrical signals, the Beidou RTK positioning module in the above-mentioned simulated γ radiation source and the simulated γ monitor obtains positioning reference information from the Beidou RTK positioning base station, and the wireless communication module in the above-mentioned simulated γ radiation source and the simulated γ monitor maintains wireless communication with the wireless communication base station. Second, build an outdoor gamma radiation monitoring simulation training field: Select an outdoor venue with specific terrain and area as a simulation training field, set up a Beidou RTK positioning base station and a wireless communication base station, and after the computer of the guidance and control center is powered on, the Beidou RTK positioning base station will transmit the Beidou positioning reference information obtained by the solution to the wireless communication base station through the optical fiber switch, and the wireless communication base station will broadcast the Beidou positioning reference information; Third, simulate the layout and parameter setting of γ radiation source: Each simulated gamma radiation source has a unique identity code (ID). When the simulated gamma radiation source is turned on and powered on, it is in a simulated radiation state. One of the ways to arrange and set parameters of simulated gamma radiation sources: according to the requirements of simulated training, personnel arrange several simulated gamma radiation sources at different points in the simulated training field, and preset the nuclide name and radioactivity intensity through the manual button of each simulated gamma radiation source parameter selection. After the simulated gamma radiation source is powered on for self-test, the simulated gamma radiation source at each point performs joint calculation by receiving the positioning reference information of Beidou RTK and combining it with the Beidou information obtained by itself, and then sends its own ID code, Beidou precise positioning information and preset parameter information through the wireless communication module; The second method of arranging and setting parameters of simulated gamma radiation sources is that when personnel arrange simulated gamma radiation sources at various points on the simulated training site and turn them on, the mobile communication module inside the simulated gamma radiation source in working state will jointly solve the received Beidou satellite signal and Beidou RTK base station signal, so that the simulated gamma radiation source can obtain centimeter-level positioning accuracy. Then, the simulated gamma radiation source automatically sends the precise positioning information (longitude, latitude and elevation) of its location to the mobile wireless communication base station through its wireless communication module, and then transmits it to the guidance and control center computer. After the guidance and control center receives the ID code and Beidou precise positioning information of the simulated gamma radiation source at each point, it sets the nuclide type and radioactivity intensity of the simulated gamma radiation source at each point in the guidance and control center computer, and sends it to each simulated gamma radiation source, and stores it in the nuclide intensity storage module. Each simulated gamma radiation source then sends its own ID code, Beidou precise positioning and parameter information through the wireless communication base station; In order to intuitively display the simulated training field and the simulated training effect, a simulated three-dimensional γ radiation field is constructed on the computer of the command and control center and displayed on the computer screen of the command and control center, and the simulated three-dimensional γ radiation field is divided into a number of 1 decimeter × 1 decimeter × 1 decimeter cubes. When the simulated γ radiation source is arranged in the simulated training field, the computer of the command and control center calculates the total simulated γ radiation dose rate data of each cube center point of the simulated three-dimensional γ radiation field according to the location of the simulated γ radiation source and the preset parameters using formula (I), formula (II) and formula (III), and stores the data in the electronic spreadsheet of the computer of the command and control center. When the location of the simulated γ monitor is in a certain cube space of the simulated three-dimensional γ radiation field, the computer of the command and control center can send the total simulated γ radiation dose rate data of the cube center point to the simulated γ monitor through wireless communication; Fourth, simulated γ monitors enter the simulated training ground for practical training: Each analog γ monitor has a unique identity code (ID). When the analog γ monitor is turned on and powered on, it is in the analog monitoring working state. (1) Finding simulated γ radiation sources: The mobile communication module of the simulated γ monitor in working state will receive the Beidou satellite signal and the Beidou RTK base station signal, and jointly calculate the centimeter-level positioning accuracy in real time. Then, the precise position information of the simulated γ radiation source in the working state and the precise position information of the simulated γ monitor itself will be substituted into formula (1) and formula (2) to calculate the distance X between the simulated γ monitor and the simulated γ radiation source, and then substitute it into formula (3) to calculate the γ radiation dose rate at a distance of X meters from the simulated γ radiation source. Substitute the other simulated γ radiation sources in the simulated training field into the above three formulas and calculate them one by one to obtain a set of γ radiation Dose rate Finally, the total gamma radiation dose rate at the precise position of the simulated gamma monitor is obtained by accumulating and summing. The acceleration sensor in the simulated gamma monitor can sense the movement and stop status of the simulated gamma monitor. Each time it stops, a new position information is calculated and provided. When the simulated gamma monitor stops at a new position, the simulated gamma monitor will jointly solve its own Beidou positioning information and the received Beidou RTK positioning reference information again to obtain the precise positioning information of the new position, and then repeat the above calculation process to obtain the total gamma radiation dose rate at the new position. When the simulated γ monitor continuously moves in the direction and route where the total γ radiation dose rate value increases, it indicates that the simulated γ monitor is gradually approaching a certain simulated γ radiation source. When a certain simulated γ radiation source is found, the precise position of the found simulated γ radiation source is reported to the guidance center by operating the power switch of the simulated γ monitor (pressing the power switch twice in quick succession). Subsequently, the power of the simulated γ radiation source is either turned off or all information of the found simulated γ radiation source is automatically shielded. When the simulated γ monitor continues to move in the direction and route where the total γ radiation dose rate value displayed on the simulated γ monitor gradually increases, the next simulated γ radiation source can be found until all simulated γ radiation sources are found. (2) Determine the gamma radiation contamination area: In the above scenario (1) of searching for a simulated gamma radiation source, when the total gamma radiation dose rate value observed by the trainee on the simulated gamma monitor reaches the safety critical value set for the simulated training subject, the trainee sends the precise location information of the simulated gamma monitor at that moment to the guidance center through the simulated gamma monitor (by pressing the power switch twice in quick succession) and makes a physical mark at that location (such as inserting a small red flag or dropping a tumbler device with positioning and sound and light alarm functions); When the simulated γ monitor moves along the same direction and route as the total γ radiation dose rate value (safety critical value), and transmits the precise positioning information of each point that reaches the total γ radiation dose rate value (safety critical value) to the guidance and control center, on the computer screen of the guidance and control center, if these points with the same total γ radiation dose rate value (safety critical value) are connected into a line, the boundary line of the simulated radioactive contamination area measured on site by the trainees can be obtained; if the physical marks made by the trainees in the simulated training field are connected, the scope of the simulated γ radiation contamination area can be marked on site; the simulated radioactive contamination boundary line obtained by theoretical calculation of the guidance and control center and the boundary line measured in the training field can be compared, thereby assessing the training level of the trainees; In the process of determining the simulated gamma radiation contamination area, the simulated gamma monitor can be carried by the trainees into the simulated training field to complete the entire simulated training process; the simulated gamma monitor can also be carried on a drone, which hovers and measures point by point at a certain height in the simulated training field, and then flies along the specified direction and route to complete the entire simulated training process; the simulated gamma monitor can also be carried on a ground robot, and the simulated gamma monitor is kept at a height of about 1 meter from the ground, measured point by point, and then moves along the specified direction and route to complete the entire simulated training process; (3) Real-time monitoring of personal cumulative dose: In the same scenario as (1) of finding a simulated gamma radiation source, a simulated gamma monitor is used to realize real-time measurement of personal cumulative dose. That is, the time from the start-up of the instrument or the completion of the previous total radiation dose rate measurement of the simulated gamma monitor to the completion of the current total radiation dose rate measurement is multiplied by the current total radiation dose rate to obtain the personal radiation dose received by the trainee in this gamma radiation measurement. The personal radiation dose received by the trainee in each gamma radiation measurement during the entire training process is added together to obtain the personal cumulative dose received by the trainee during this simulated training. When the personal cumulative dose reaches the threshold value that is harmful to the human body, the simulated gamma monitor can alarm. During the simulated training process, the simulated gamma monitor can also display the personal cumulative dose value in real time.

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