CN109471147B - Gamma dose rate calculation method and system based on variable weight dispersion - Google Patents
Gamma dose rate calculation method and system based on variable weight dispersion Download PDFInfo
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Abstract
The invention discloses a gamma dose rate calculation method and a system based on variable weight dispersion, wherein the method comprises the following steps: s1, respectively establishing X, Y, Z coordinate axes by taking the geometric center of a source or a surface source as an origin; s2, setting discrete weight parameters according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction; s3, dispersing the source or the surface source into a plurality of point sources; s4, calculating the gamma dose rate contribution of each point source; s5, accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the point source or the surface source at the point to be calculated; and S6, accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated. The method and the system provided by the invention adopt different weights according to different distances between points and the source, so that the corresponding discrete numbers of the source and the surface source are different, the calculation precision of the gamma external irradiation dose rate is ensured, and the calculation efficiency can be greatly improved.
Description
Technical Field
The invention relates to the technical field of radiation protection, in particular to a gamma dose rate calculation method and system based on variable weight dispersion.
Background
The point-kernel integration method is a common method for calculating gamma external irradiation dose, is widely applied to shielding calculation and external irradiation dose calculation, and compared with a Monte Carlo method, the method is not limited by space size and shielding body thickness, has small time consumption and higher calculation speed, and has the defects that the method cannot accurately consider the particle scattering problem, accumulation factors need to be introduced to correct the particle scattering, and the calculation result is always conservative.
The method is based on the calculation of the isotropic point source, converts the source or the surface source into a plurality of isotropic point sources by adopting a discrete method, and accumulates the calculation result of each point source to obtain the calculation result of the whole source or the surface source. The number of discrete point sources, either source or area sources, is not only related to the accuracy of the calculation, but also to the required calculation time. On one hand, the traditional point-kernel integration algorithm does not optimize the calculation efficiency, and the calculation speed can not meet the current requirement, on the other hand, the advantages of the point-kernel integration method in the gamma radiation field calculation are shown, and meanwhile, the quantity of the dot matrixes representing the three-dimensional radiation field to be calculated is more and more huge along with the requirement of the radiation field visual display, which provides a serious challenge to the calculation speed.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a gamma dose rate calculation method and system based on variable weight dispersion, wherein different weights are adopted to disperse a source or a surface source according to different distances between calculation points and the source, so that the calculation efficiency of a gamma radiation field is improved on the premise of ensuring the calculation accuracy.
In order to realize the purpose, the technical scheme adopted by the invention is as follows:
a gamma dose rate calculation method based on variable weight dispersion comprises the following steps:
s1, establishing a local coordinate system in an integrated source or a surface source, and respectively establishing a X, Y, Z coordinate axis by taking the geometric center of the source or the surface source as an origin;
s2, calculating the distance from a point to be calculated to each coordinate axis, and setting a discrete weight parameter according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
s3, dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the dispersion weight parameters;
s4, calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
s5, accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the point source or the surface source at the point to be calculated;
and S6, accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated.
Further, as described above, in the method for calculating a gamma dose rate based on variable weight discretization, step S3 includes:
s31, calculating to obtain discrete numbers of the points to be calculated in the directions of the coordinate axes according to the distances from the points to be calculated to the coordinate axes, the maximum size and the discrete weight parameters;
s32, obtaining the smaller discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and calculation, and taking the smaller discrete number as the final discrete number of the point to be calculated in each coordinate axis direction;
s33, dispersing the source or the surface source into a plurality of point sources, wherein the number of the point sources is the product of the final dispersion numbers of the points to be calculated in the directions of the coordinate axes.
Further, as described above, in the variable weight discretization-based γ dose rate calculating method, the step S31 specifically includes:
if R is i If not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Wherein n is the discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i For the distance from the point to be calculated to each coordinate axisFrom, N i Is the discrete number, N, of the point to be calculated in the direction of the i coordinate axis i Is a positive integer, i = { i | x, y, z };
if R is i If the number of the points to be calculated is not less than 0, namely the points to be calculated are located on a coordinate axis, calculating according to the following formula and rounding up to obtain a discrete number N of the points to be calculated in the direction of the coordinate axis;
wherein N is the discrete weight parameter, R is the distance from the point to be calculated to the origin, D is the maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer.
Further, in the above-mentioned method for calculating a gamma dose rate based on variable weight discretization, in step S2, a discretization weight parameter n is set according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction, and specifically includes:
if it is not
The value of n is set to
If it is not
The value of n is set to any number between 10 and 20 depending on the actual situation;
if it is not
The value of n is set to any number between 1 and 10 according to actual conditions;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i I = { i | x, y, z } for the distance of the point to be calculated to each coordinate axis.
Further, in the above method for calculating a gamma dose rate based on variable weight dispersion, step S4 specifically includes:
calculating the gamma dose rate contribution of each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Is the activity of the ith point source, B is the cumulative factor, e -μt Is an exponential attenuation term, mu is the linear attenuation coefficient of the material to gamma photons, t is the distance of the gamma photons passing through the material, r is the distance from the ith point source to the point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
The embodiment of the invention also provides a gamma dose rate calculation system based on variable weight dispersion, which comprises:
the establishing module is used for establishing a local coordinate system in the integrated source or the one-surface source, and respectively establishing X, Y, Z coordinate axes by taking the geometric center of the source or the surface source as an origin;
the setting module is used for calculating the distance from a point to be calculated to each coordinate axis and setting discrete weight parameters according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
the discrete module is used for dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameters;
the calculation module is used for calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
the first accumulation module is used for accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the source or the area source at the point to be calculated;
and the second accumulation module is used for accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated.
Further, a variable weight discretization based gamma dose rate calculation system as described above, the discretization module comprising:
the calculation submodule is used for calculating to obtain the discrete number of the point to be calculated in each coordinate axis direction according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameter;
the determining submodule is used for obtaining the smaller discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and the discrete number of the point to be calculated in each coordinate axis direction through calculation, and the smaller discrete number is used as the final discrete number of the point to be calculated in each coordinate axis direction;
and the discrete sub-module is used for dispersing the source or the surface source into a plurality of point sources, and the number of the point sources is the product of the final discrete number of the points to be calculated in each coordinate axis direction.
Further, as described above, the calculation submodule is specifically configured to:
if R is i Not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Wherein n is the discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i Is the distance, N, from the point to be calculated to each coordinate axis i Is the discrete number, N, of the point to be calculated in the direction of the i coordinate axis i Is a positive integer, i = { i | x, y, z };
if R is i =0, namely the point to be calculated is located on the coordinate axis, the discrete number N of the point to be calculated in the coordinate axis direction is obtained after calculation according to the following formula and rounding up;
wherein N is the discrete weight parameter, R is the distance from the point to be calculated to the origin, D is the maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer.
Further, as described above, the setting module is specifically configured to:
if it is not
The value of n is set to
If it is not
The value of n is set to any number between 10 and 20 depending on the actual situation;
if it is not
The value of n is set to any number between 1 and 10 according to actual conditions;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i And i = { i | x, y, z } for the distance from the point to be calculated to each coordinate axis.
Further, as described above, the first accumulation module is specifically configured to:
calculating the gamma dose rate contribution for each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Is the ith point sourceActivity of (D), B is a cumulative factor, e -μt Is an exponential attenuation term, mu is the linear attenuation coefficient of the material to gamma photons, t is the distance of the gamma photons passing through the material, r is the distance from the ith point source to the point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
The invention has the beneficial effects that: according to the method and the system provided by the invention, different weights are adopted according to different distances from the source to the source, so that the corresponding discrete numbers of the source and the non-point source are different, for the calculation points in the region far away from the source, the small discrete numbers can achieve high calculation accuracy, and for the region near the source, the large discrete numbers are needed to achieve the corresponding calculation accuracy. Not only the precision of gamma external irradiation dosage rate calculation is ensured, but also the calculation efficiency is greatly improved.
Drawings
Fig. 1 is a schematic flowchart of a gamma dose rate calculation method based on variable weight discretization according to an embodiment of the present disclosure;
fig. 2 is a schematic structural diagram of a gamma dose rate calculation system based on variable weight discretization provided in an embodiment of the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and the detailed description.
As shown in fig. 1, a method for calculating a gamma dose rate based on variable weight discretization includes:
s1, establishing a local coordinate system in an integrated source or a surface source, and respectively establishing a X, Y, Z coordinate axis by taking the geometric center of the source or the surface source as an origin;
s2, calculating the distance from a point to be calculated to each coordinate axis, and setting a discrete weight parameter according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
s3, dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the dispersion weight parameters;
s4, calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
s5, accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the point source or the surface source at the point to be calculated;
and S6, accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated.
The step S3 comprises the following steps:
s31, calculating to obtain discrete numbers of the points to be calculated in the directions of the coordinate axes according to the distances from the points to be calculated to the coordinate axes, the maximum sizes and the discrete weight parameters;
s32, obtaining the smaller discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and calculation, and taking the smaller discrete number as the final discrete number of the point to be calculated in each coordinate axis direction;
s33, dispersing the source or the surface source into a plurality of point sources, wherein the number of the point sources is the product of the final dispersion numbers of the points to be calculated in the directions of the coordinate axes.
Step S31 specifically includes:
if R is i Not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Where n is a discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i For the distance of the point to be calculated to each coordinate axis, N i Is a discrete number of points to be calculated in the direction of the i coordinate axis, N i Is a positive integer, i = { i | x, y, z };
if R is i =0, namely the point to be calculated is located on the coordinate axis, the discrete number N of the point to be calculated in the coordinate axis direction is obtained after calculation according to the following formula and rounding up;
wherein N is a discrete weight parameter, R is a distance from a point to be calculated to an origin, D is a maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer.
In step S2, a discrete weight parameter n is set according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction, and specifically includes:
if it is not
The value of n is set to
If it is not
The value of n is set to any number between 10 and 20 depending on the actual situation;
if it is not
The value of n is set to any number between 1 and 10 according to actual conditions;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i I = { i | x, y, z } for the distance of the point to be calculated to each coordinate axis.
Step S4 specifically includes:
calculating the gamma dose rate contribution of each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Activity of the ith point source, B is a cumulative factor, e -μt Is an exponential decay term, mu is the linear decay coefficient of the material to gamma photons, t is the distance that gamma photons travel through the material, and r is the ithDistance of point source to point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
The greater the discrete number of sources or area sources, the more accurate the radiation field data will be. With the increase of the discrete number, the error between the calculated value and the analytic solution is smaller and smaller, and after the discrete number is increased to a certain degree, the error between the calculated value and the analytic solution tends to 0, the discrete number is further increased, the calculation precision cannot be improved, but the time required by calculation is greatly increased, and meanwhile, with the increase of the distance between the calculated value and the source, the discrete number required when the calculated value tends to be stable also gradually becomes smaller, so the calculation precision and the time are comprehensively considered, a weight discrete method is adopted in the text, namely, a larger discrete number is adopted for the calculated point in a region closer to the source or the area source; for calculation points that are farther away from the source or the area of the surface source, a smaller discrete number is used. In the radiation field calculation, weight dispersion is adopted for the source, and an appropriate dispersion weight parameter n can be selected according to actual calculation requirements by comprehensively considering the distance from a calculation point to the surface of the source and the maximum size of the source.
Example one
A staircase geometry was 6.3m 4.25m 9.3m and was divided into 9300 gamma dose rate points to be calculated at intervals of high length, width, etc. within the site. The source has a pipeline surface source which is uniformly distributed on the inner wall of the pipeline, the activity is 109Bq, the energy is 1.173MeV, the outer radius of the pipeline is 20cm, the inner radius is 19cm, the height is 200cm, the source is positioned on a second-layer step, and the influence of the wall thickness is ignored. After the method is adopted, variable weight dispersion is adopted for the pipeline surface source items, 20 are taken as the dispersion weight parameter n in the height direction, and the calculation time ratio of the optimized calculation method and the traditional method on the same computer is shown in the following table. After the variable weight discrete optimization method is adopted, the calculation time is reduced to about 1/3 of the original calculation time.
Meanwhile, in order to compare the calculation results of the two points, 600 calculation point positions are selected in the area near the source, the average deviation between the two points is 1.32%, and the maximum deviation is 4.02%; 900 calculation points are selected in a region far away from a source, the average deviation between the calculation points is 0.61%, and the maximum deviation is 3.55%. The calculation deviation of the degree is enough to meet the calculation requirement of the gamma radiation field on site.
It can be seen that the method for optimizing the computation efficiency provided herein can not only effectively improve the computation efficiency of the gamma radiation field, but also correspondingly ensure the computation accuracy of the result.
As shown in fig. 2, an embodiment of the present invention further provides a gamma dose rate calculation system based on variable weight discretization, including:
the establishing module 1 is used for establishing a local coordinate system in the integrated source or the one-surface source, and respectively establishing X, Y, Z coordinate axes by taking the geometric center of the source or the surface source as an origin;
the setting module 2 is used for calculating the distance from a point to be calculated to each coordinate axis and setting discrete weight parameters according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
the discrete module 3 is used for dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameters;
the calculation module 4 is used for calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
the first accumulation module 5 is configured to accumulate the gamma dose rate contribution of each point source to obtain the gamma dose rate of the source or the area source at the point to be calculated;
and the second accumulation module 6 is used for accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated.
The discrete module 3 includes:
the calculation submodule is used for calculating to obtain the discrete number of the point to be calculated in each coordinate axis direction according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameter;
the determining submodule is used for obtaining the smaller discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and the discrete number of the point to be calculated in each coordinate axis direction through calculation, and the smaller discrete number is used as the final discrete number of the point to be calculated in each coordinate axis direction;
and the discrete sub-module is used for dispersing the source or the surface source into a plurality of point sources, and the number of the point sources is the product of the final discrete number of the points to be calculated in each coordinate axis direction.
The calculation submodule is specifically configured to:
if R is i Not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Wherein n is a discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i Is the distance of the point to be calculated from each coordinate axis, N i Is a discrete number of points to be calculated in the direction of the i coordinate axis, N i Is a positive integer, i = { i | x, y, z };
if R is i =0, namely the point to be calculated is located on the coordinate axis, the discrete number N of the point to be calculated in the coordinate axis direction is obtained after calculation according to the following formula and rounding up;
wherein N is a discrete weight parameter, R is a distance from a point to be calculated to an origin, D is a maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer.
The setting module 2 is specifically configured to:
if it is used
The value of n is set to
If it is not
The value of n is set to any number between 10 and 20 depending on the actual situation;
if it is used
The value of n is set to any number between 1 and 10 according to actual conditions;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i I = { i | x, y, z } for the distance of the point to be calculated to each coordinate axis.
The first accumulation module 5 is specifically configured to:
calculating the gamma dose rate contribution of each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Activity of the ith point source, B is a cumulative factor, e -μt Is an exponential attenuation term, mu is the linear attenuation coefficient of the material to gamma photons, t is the distance of the gamma photons passing through the material, r is the distance from the ith point source to the point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.
Claims (4)
1. A gamma dose rate calculation method based on variable weight dispersion is characterized by comprising the following steps:
s1, establishing a local coordinate system in an integrated source or a surface source, and respectively establishing a X, Y, Z coordinate axis by taking the geometric center of the source or the surface source as an origin;
s2, calculating the distance from a point to be calculated to each coordinate axis, and setting a discrete weight parameter according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
s3, dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the dispersion weight parameters;
s4, calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
s5, accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the point source or the surface source at the point to be calculated;
s6, accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated;
the step S3 comprises the following steps:
s31, calculating to obtain discrete numbers of the points to be calculated in the directions of the coordinate axes according to the distances from the points to be calculated to the coordinate axes, the maximum size and the discrete weight parameters;
s32, obtaining the smaller of the discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and the discrete number of the point to be calculated in each coordinate axis direction through calculation, and taking the smaller of the discrete numbers as the final discrete number of the point to be calculated in each coordinate axis direction;
s33, dispersing the source or the surface source into a plurality of point sources, wherein the number of the point sources is the product of the final dispersion numbers of the points to be calculated in the directions of the coordinate axes;
step S31 specifically includes:
if R is i Not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Wherein n is the discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i Is the distance, N, from the point to be calculated to each coordinate axis i Is the discrete number, N, of the point to be calculated in the direction of the i coordinate axis i Is a positive integer, i = { i | x, y, z };
if R is i If the number of the points to be calculated is not less than 0, namely the points to be calculated are located on a coordinate axis, calculating according to the following formula and rounding up to obtain a discrete number N of the points to be calculated in the direction of the coordinate axis;
wherein N is the discrete weight parameter, R is the distance from the point to be calculated to the origin, D is the maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer;
in step S2, a discrete weight parameter n is set according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction, which specifically includes:
if it is not
The value of n is set to
If it is not
The value of n is set to any number between 10-20 depending on the actual situation;
if it is not
The value of n is set to any number between 1-10 depending on the actual situation;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i And i = { i | x, y, z } for the distance from the point to be calculated to each coordinate axis.
2. The method for calculating gamma dose rate based on variable weight discretization as claimed in claim 1, wherein the step S4 specifically comprises:
calculating the gamma dose rate contribution of each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Activity of the ith point source, B is a cumulative factor, e -μt Is an exponential attenuation term, mu is the linear attenuation coefficient of the material to gamma photons, t is the distance of the gamma photons passing through the material, r is the distance from the ith point source to the point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
3. A system for calculating gamma dose rate based on variable weight discretization, comprising:
the establishing module is used for establishing a local coordinate system in the integrated source or the one-surface source, and respectively establishing X, Y, Z coordinate axes by taking the geometric center of the source or the surface source as an origin;
the setting module is used for calculating the distance from a point to be calculated to each coordinate axis and setting discrete weight parameters according to the distance from the point to be calculated to each coordinate axis and the maximum size of the source or the surface source in each coordinate axis direction;
the discrete module is used for dispersing the source or the surface source into a plurality of point sources according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameters;
the calculation module is used for calculating the gamma dose rate contribution of each point source according to the distance from each point source to the point to be calculated;
the first accumulation module is used for accumulating the gamma dose rate contribution of each point source to obtain the gamma dose rate of the source or the area source at the point to be calculated;
the second accumulation module is used for accumulating the gamma dose rates of each source and each surface source at the point to be calculated to obtain the final gamma dose rate of the point to be calculated;
the discrete module comprises:
the calculation submodule is used for calculating to obtain the discrete number of the point to be calculated in each coordinate axis direction according to the distance from the point to be calculated to each coordinate axis, the maximum size and the discrete weight parameter;
the determining submodule is used for obtaining the smaller discrete number of the point to be calculated in each coordinate axis direction from the preset maximum discrete number in each coordinate axis direction and the discrete number of the point to be calculated in each coordinate axis direction through calculation, and the smaller discrete number is used as the final discrete number of the point to be calculated in each coordinate axis direction;
the discrete sub-module is used for dispersing the source or the surface source into a plurality of point sources, and the number of the point sources is the product of the final discrete number of the points to be calculated in each coordinate axis direction;
the calculation submodule is specifically configured to:
if R is i Not equal to 0, calculating according to the following formula and rounding upwards to obtain the discrete number N of the point to be calculated in each coordinate axis direction i ；
Wherein n is the discrete weight parameter, D i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i Is the distance, N, from the point to be calculated to each coordinate axis i Is the discrete number, N, of the point to be calculated in the direction of the i coordinate axis i Is a positive integer, i = { i | x, y, z };
if it is notR i If the number of the points to be calculated is not less than 0, namely the points to be calculated are located on a coordinate axis, calculating according to the following formula and rounding up to obtain a discrete number N of the points to be calculated in the direction of the coordinate axis;
wherein N is the discrete weight parameter, R is the distance from the point to be calculated to the origin, D is the maximum size of the source or the surface source in the coordinate axis direction, and N is a positive integer;
the setting module is specifically configured to:
if it is not
The value of n is set to
If it is not
The value of n is set to any number between 10-20 depending on the actual situation;
if it is not
The value of n is set to any number between 1-10 depending on the actual situation;
wherein D is i Is the maximum dimension, R, of the source or the surface source in the direction of each coordinate axis i And i = { i | x, y, z } for the distance from the point to be calculated to each coordinate axis.
4. The variable weight discretization based gamma dose rate computing system of claim 3, wherein the first accumulating module is further configured to:
calculating the gamma dose rate contribution of each point source according to the following formula;
wherein F (E) is the transfer function, E is the energy of the gamma photon, A i Activity of the ith point source, B is a cumulative factor, e -μt Is an exponential attenuation term, mu is the linear attenuation coefficient of the material to gamma photons, t is the distance of the gamma photons passing through the material, r is the distance from the ith point source to the point to be calculated, H i The gamma dose rate contribution for the ith point source, i being a positive integer.
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Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0824697A1 (en) * | 1995-04-18 | 1998-02-25 | Wyntek Diagnostics, Inc. | One step immunochromatographic device and method of use |
| WO2003046611A1 (en) * | 2001-11-27 | 2003-06-05 | Bnfl (Ip) Ltd | Environmental radiation detector |
| EP2167971A2 (en) * | 2007-07-19 | 2010-03-31 | bioMérieux | Ezrin assay method for the in vitro diagnosis of colorectal cancer |
| WO2011019303A1 (en) * | 2009-08-13 | 2011-02-17 | Закрытое Акционерное Общество "Hayчнo-Пpoизвoдcтвeннaя Коммерческая Фирма "Элtah Лtд" | Multi-element x-ray radiation detector, rare earth x-ray luminophore therefor, and method for forming a multi-element scintillator and detector as a whole |
| EP2556389A1 (en) * | 2010-04-09 | 2013-02-13 | Isp Investments Inc. | Radiation dosimetry method |
| CN104483693A (en) * | 2014-12-24 | 2015-04-01 | 西北核技术研究所 | Non-uniform distributed source detection efficiency calculation and simulation device and method |
| CN105092612A (en) * | 2014-05-06 | 2015-11-25 | 阿斯特菲公司 | Computed tomography system for cargo and transported containers |
| WO2016012620A1 (en) * | 2014-07-24 | 2016-01-28 | Dosevue Nv | Direct surface radiation dose measurement system with quantitative optical read-out |
| CN106061541A (en) * | 2014-02-27 | 2016-10-26 | 皇家飞利浦有限公司 | System for applying radiation to a target region within a subject |
| CN106199676A (en) * | 2015-04-30 | 2016-12-07 | 北京中智核安科技有限公司 | A kind of gamma detector passive efficiency scale new method |
| CN106814384A (en) * | 2015-11-27 | 2017-06-09 | 华北电力大学 | Nuclear power plant's point source radiation source strength backstepping method and point source radiation source strength backstepping system |
| CN106932810A (en) * | 2017-04-01 | 2017-07-07 | 西安体医疗科技有限公司 | A kind of convolutional calculation method of gamma rays dosage |
| CN107290769A (en) * | 2016-04-12 | 2017-10-24 | 华北电力大学 | The recombination radiation source strength backstepping method and system of nuclear power plant's point source body source combination |
| CN108287357A (en) * | 2018-01-15 | 2018-07-17 | 东华理工大学 | A kind of source peak detection efficient acquisition methods of cylinder bulk detector to point source |
| CN108549753A (en) * | 2018-03-28 | 2018-09-18 | 中国船舶重工集团公司第七〇九研究所 | A kind of radiation shield computational methods that Point- kernel integral method is coupled with Monte Carlo method |
| CA3076763A1 (en) * | 2017-10-20 | 2019-04-25 | Australian Nuclear Science And Technology Organisation | Compressive imaging method and system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8423125B2 (en) * | 2004-11-09 | 2013-04-16 | Spectrum Dynamics Llc | Radioimaging |
| US8666711B2 (en) * | 2006-03-17 | 2014-03-04 | Canberra Industries, Inc. | Radiation analysis system and method |
-
2018
- 2018-09-25 CN CN201811115395.4A patent/CN109471147B/en active Active
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0824697A1 (en) * | 1995-04-18 | 1998-02-25 | Wyntek Diagnostics, Inc. | One step immunochromatographic device and method of use |
| WO2003046611A1 (en) * | 2001-11-27 | 2003-06-05 | Bnfl (Ip) Ltd | Environmental radiation detector |
| EP2167971A2 (en) * | 2007-07-19 | 2010-03-31 | bioMérieux | Ezrin assay method for the in vitro diagnosis of colorectal cancer |
| WO2011019303A1 (en) * | 2009-08-13 | 2011-02-17 | Закрытое Акционерное Общество "Hayчнo-Пpoизвoдcтвeннaя Коммерческая Фирма "Элtah Лtд" | Multi-element x-ray radiation detector, rare earth x-ray luminophore therefor, and method for forming a multi-element scintillator and detector as a whole |
| EP2556389A1 (en) * | 2010-04-09 | 2013-02-13 | Isp Investments Inc. | Radiation dosimetry method |
| CN106061541A (en) * | 2014-02-27 | 2016-10-26 | 皇家飞利浦有限公司 | System for applying radiation to a target region within a subject |
| CN105092612A (en) * | 2014-05-06 | 2015-11-25 | 阿斯特菲公司 | Computed tomography system for cargo and transported containers |
| WO2016012620A1 (en) * | 2014-07-24 | 2016-01-28 | Dosevue Nv | Direct surface radiation dose measurement system with quantitative optical read-out |
| CN104483693A (en) * | 2014-12-24 | 2015-04-01 | 西北核技术研究所 | Non-uniform distributed source detection efficiency calculation and simulation device and method |
| CN106199676A (en) * | 2015-04-30 | 2016-12-07 | 北京中智核安科技有限公司 | A kind of gamma detector passive efficiency scale new method |
| CN106814384A (en) * | 2015-11-27 | 2017-06-09 | 华北电力大学 | Nuclear power plant's point source radiation source strength backstepping method and point source radiation source strength backstepping system |
| CN107290769A (en) * | 2016-04-12 | 2017-10-24 | 华北电力大学 | The recombination radiation source strength backstepping method and system of nuclear power plant's point source body source combination |
| CN106932810A (en) * | 2017-04-01 | 2017-07-07 | 西安体医疗科技有限公司 | A kind of convolutional calculation method of gamma rays dosage |
| CA3076763A1 (en) * | 2017-10-20 | 2019-04-25 | Australian Nuclear Science And Technology Organisation | Compressive imaging method and system |
| CN108287357A (en) * | 2018-01-15 | 2018-07-17 | 东华理工大学 | A kind of source peak detection efficient acquisition methods of cylinder bulk detector to point source |
| CN108549753A (en) * | 2018-03-28 | 2018-09-18 | 中国船舶重工集团公司第七〇九研究所 | A kind of radiation shield computational methods that Point- kernel integral method is coupled with Monte Carlo method |
Non-Patent Citations (10)
| Title |
|---|
| Calculation Method for Gamma Dose Rates From Gaussian Puffs;S. Thykier-Nielsen;《RISO》;19951231;第1-12页 * |
| FFT-BP神经网络模型对车载γ能谱辐射剂量率的预测分析;徐立鹏等;《光谱学与光谱分析》;20180215;第38卷(第02期);第590-594页 * |
| Gamma radiation measurements and dose rates in commercially-used natural tiling rocks (granites);Michalis Tzortzis.et;《UCY−PHY》;20021231;第1-22页 * |
| GaP: A Factor Model for Discrete Data;John Canny;《ACM》;20041231;第1-8页 * |
| GPU-based fast gamma index calculation;Xuejun Gu.et;《Phys Med Biol》;20111231;第1431-1441页 * |
| Multiquadric散乱数据插值方法在γ辐射场可视化中的应用初探;赛雪等;《核技术》;20161231;第39卷(第10期);第55-61页 * |
| SCALE5.1程序系统中蒙特卡罗方法模块与离散纵坐标模块在乏燃料运输容器屏蔽计算中的比较分析;张普忠等;《辐射防护》;20101130;第30卷(第6期);第373-378页 * |
| Slide Rule for Rapid Response Estimation of Radiological Dose from Criticality Accidents;C. M. Hopper.et;《Computational Physics and Engineering Division》;19991231;第1-12页 * |
| Software Application for Gamma Ray Computed Tomography Data Acquisition with Discrete Detectors;Rajesh Acharya.et;《Software Application for Gamma Ray Computed Tomography Data》;20190101;第1-8页 * |
| 基于MCNP对γ射线吸收剂量累积因子的计算与研究;李华等;《辐射防护》;20171231;第161-168页 * |
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