Algorithm for a wireless, motion and position-sensing, integrating radiation sensor for occupational and environmental dosimetry

• US 9,057,786 B2
• Filed: 05/28/2014
• Issued: 06/16/2015
• Est. Priority Date: 06/01/2012
• Status: Active Grant

• Current Assignee: Landauer, Inc. (Fortive Corp.)
• Original Assignee: Landauer, Inc. (Fortive Corp.)
• Inventors: Walerow, P. Alexander, Salasky, Mark R., Valentino, Daniel J., Moreno, Brahim, Million, Marc
• Primary Examiner(s): Kim, Kiho
• Application Number:
  US14/288,822
• Publication Number:
  US 20140278261A1
• Time in Patent Office: 384 Days
• US Class Current: 1/1
• CPC Class Codes: G01T 1/02 Dosimeters G01T1/15 takes precedence
• CPC Class Codes: G01T 7/00 Details of radiation-measuring instruments

Abstract

Described is an apparatus, method and machine-readable medium for determining radiation dosages based on a solution vector for each radiation field and an objective function.

Claims

1. An apparatus comprising:

one or more processors, and a machine-readable medium for storing instructions thereon which when executed by the one or more processors cause the one or more processors to perform operations comprising the following steps;

(a) determining radiation dose values for a response matrix by determining a radiation dose value for each radiation field in a response matrix from a plurality of detector elements of a dosimeter,

(b) determining a final net radiation dose value for each radiation field in the response matrix, and

(c) displaying the final net radiation dose value for each radiation field in the response matrix to a user and/or saving the final net radiation dose value for each radiation field to a first storage medium,

wherein each radiation field has a radiation source,

wherein step (b) comprises conducting a numerical optimization process comprising the following steps;

(i) generating an initial solution vector for each radiation field,

(ii) iteratively updating the initial solution vector for each radiation field until an objective function is minimized to thereby generate an optimal solution vector, and

(iii) determining a radiation dose value for each radiation field based on the optimal solution vector for the source,

wherein the objective function is

2. The apparatus of claim 1, wherein the machine-readable medium, the first storage medium and the second storage medium are the same storage medium.

3. The apparatus of claim 1, wherein step (b) comprises the following steps:

(d) checking error conditions for each final radiation dose value to thereby determine if error conditions exist for each radiation dose value, and

(e) displaying the error conditions determined in step (d) to the user and/or saving the error conditions determined in step (d) to the first storage medium.

4. The apparatus of claim 1, wherein step (b) comprises assessing radiation quality of the radiation dose values.

5. The apparatus of claim 1, wherein step (b) comprises determining an accurate assessment of ionizing radiation dose with an optimized data-fitting procedure.

6. The apparatus of claim 1, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a response matrix weighting factor.

7. The apparatus of claim 1, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on:

a product of a response matrix weighting factor, an expected source dose, and a dose conversion factor for the radiation field.

8. The apparatus of claim 1, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on personal dose equivalent values for H_p(10 mm), H_p(0.07 mm), and H_p(3 mm) for each radiation field.

9. The apparatus of claim 1, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a background dose for the radiation field.

10. The apparatus of claim 1, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on one or more noise sample for the dosimeter.

11. The apparatus of claim 1, wherein step (c) comprises displaying dosimeter readout data, background dose data, and response matrix data.

12. The apparatus of claim 1, wherein step (c) comprises saving dosimeter readout data, background dose data, and response matrix data to the second storage medium.

13. The apparatus of claim 1, wherein step (c) comprises displaying dose distributions for each radiation field to the user.

14. The apparatus of claim 1, wherein step (c) comprises saving dose distributions for each radiation field to the second storage medium.

15. The apparatus of claim 1, wherein step (c) comprises displaying the final net radiation dose value for each radiation field in the response matrix to the user.

16. The apparatus of claim 1, wherein step (c) comprises saving the final net radiation dose value for each radiation field in the response matrix to the first storage medium.

17. A non-transitory machine-readable medium having stored thereon sequences of instructions, which when executed by one or more processors, cause one or more electronic devices to perform a set of operations comprising the following steps:

(a) determining radiation dose values for a response matrix by determining a radiation dose value for each radiation field in a response matrix from a plurality of detector elements of a dosimeter,

(b) determining a final net radiation dose value for each radiation field in the response matrix, and

(c) displaying the final net radiation dose value for each radiation field in the response matrix to a user and/or saving the final net radiation dose value for each radiation field to a first storage medium,

wherein each radiation field has a radiation source,

wherein step (b) comprises conducting a numerical optimization process comprising the following steps;

(i) generating an initial solution vector for each radiation field,

(ii) iteratively updating the initial solution vector for each radiation field until an objective function is minimized to thereby generate an optimal solution vector, and

(iii) determining a radiation dose value for each radiation field based on the optimal solution vector for the source,

wherein the objective function is

18. The non-transitory machine-readable medium of claim 17, wherein the machine-readable medium, the first storage medium and the second storage medium are the same storage medium.

19. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises the following steps:

(d) checking error conditions for each final radiation dose value to thereby determine if error conditions exist for each radiation dose value, and (e) displaying the error conditions determined in step (d) to the user and/or saving the error conditions determined in step (d) to the first storage medium.

20. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises assessing radiation quality of the radiation dose values.

21. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining an accurate assessment of ionizing radiation dose with an optimized data-fitting procedure.

22. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a response matrix weighting factor.

23. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on:

a product of a response matrix weighting factor, an expected source dose, and a dose conversion factor for the radiation field.

24. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on personal dose equivalent values for H_p(10 mm), H_p(0.07 mm), and H_p(3 mm) for each radiation field.

25. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a background dose for the radiation field.

26. The non-transitory machine-readable medium of claim 17, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on one or more noise sample for the dosimeter.

27. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises displaying dosimeter readout data, background dose data, and response matrix data.

28. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises saving dosimeter readout data, background dose data, and response matrix data to the second storage medium.

29. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises displaying dose distributions for each radiation field to the user.

30. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises saving dose distributions for each radiation field to the second storage medium.

31. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises displaying the final net radiation dose value for each radiation field in the response matrix to the user.

32. The non-transitory machine-readable medium of claim 17, wherein step (c) comprises saving the final net radiation dose value for each radiation field in the response matrix to the first storage medium.

33. A method comprising the following steps:

(a) determining radiation dose values for a response matrix by determining a radiation dose value for each radiation field in a response matrix from a plurality of detector elements of a dosimeter,

(b) determining a final net radiation dose value for each radiation field in the response matrix, and

(c) displaying the final net radiation dose value for each radiation field in the response matrix to a user and/or saving the final net radiation dose value for each radiation field to a first storage medium,

wherein each radiation field has a radiation source,

wherein step (b) comprises conducting a numerical optimization process comprising the following steps;

(i) generating an initial solution vector for each radiation field,

(ii) iteratively updating the initial solution vector for each radiation field until an objective function is minimized to thereby generate an optimal solution vector, and

(iii) determining a radiation dose value for each radiation field based on the optimal solution vector for the source,

wherein the objective function is

34. The method of claim 33, wherein the machine-readable medium, the first storage medium and the second storage medium are the same storage medium.

35. The method of claim 33, wherein step (b) comprises the following steps:

(d) checking error conditions for each final radiation dose value to thereby determine if error conditions exist for each radiation dose value, and

(e) displaying the error conditions determined in step (d) to the user and/or saving the error conditions determined in step (d) to the first storage medium.

36. The method of claim 33, wherein step (b) comprises assessing radiation quality of the radiation dose values.

37. The method of claim 33, wherein step (b) comprises determining an accurate assessment of ionizing radiation dose with an optimized data-fitting procedure.

38. The method of claim 33, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a response matrix weighting factor.

39. The method of claim 33, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on:

a product of a response matrix weighting factor, an expected source dose, and a dose conversion factor for the radiation field.

40. The method of claim 33, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on personal dose equivalent values for H_p(10 mm), H_p(0.07 mm), and H_p(3 mm) for each radiation field.

41. The method of claim 33, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on a background dose for the radiation field.

42. The method of claim 33, wherein step (b) comprises determining the final net radiation dose value for each radiation field in the response matrix based on one or more noise sample for the dosimeter.

43. The method of claim 33, wherein step (c) comprises displaying dosimeter readout data, background dose data, and response matrix data.

44. The method of claim 33, wherein step (c) comprises saving dosimeter readout data, background dose data, and response matrix data to the second storage medium.

45. The method of claim 33, wherein step (c) comprises displaying dose distributions for each radiation field to the user.

46. The method of claim 33, wherein step (c) comprises saving dose distributions for each radiation field to the second storage medium.

47. The method of claim 33, wherein step (c) comprises displaying the final net radiation dose value for each radiation field in the response matrix to the user.

48. The method of claim 33, wherein step (c) comprises saving the final net radiation dose value for each radiation field in the response matrix to the first storage medium.