Inverse ratio of gamma-ray and neutron emissions in the detection of radiation shielding of containers

• US 20050275545A1
• Filed: 07/23/2004
• Published: 12/15/2005
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Veritainer Asset Holding LLC
• Original Assignee: John I Alioto, Kenneth Greer
• Inventors: Alioto, John I., Greer, Kenneth
• Granted Patent: US 7,116,235 B2
• Time in Patent Office: Days
• US Class Current: 340/600
• CPC Class Codes: B66C 19/002 Container cranes B66C19/007 takes precedence
• CPC Class Codes: G01T 1/167 Measuring radioactive content of objects, e.g. contamination whole body counters G01T1/163
• CPC Class Codes: G01V 5/0075 Passive interrogation for hand, feet or portals G01T1/167; for contaminated surface areas G01T1/169
• CPC Class Codes: G01V 5/0091 detecting special nuclear material [SNM], e.g. Uranium-235, Uranium-233 or Plutonium-239
• CPC Class Codes: G01V 5/26 Passive interrogation, i.e. by measuring radiation emitted by objects or goods
• CPC Class Codes: G01V 5/281 detecting special nuclear material [SNM], e.g. Uranium-235, Uranium-233 or Plutonium-239
• CPC Class Codes: G08B 31/00 Predictive alarm systems characterised by extrapolation or other computation using updated historic data

Abstract

The presence of radiation shielding material concealing illegitimate content in a container is detected by obtaining each of measured gamma-ray data and measured neutron data from the container, and comparing the measured gamma-ray and neutron data to expected gamma-ray and neutron data. An anomaly between the measured data and the expected data is an indicum of the presence of such material shielding such illegitimate content.

Claims

1. A method to determine the presence of radiation shielding material concealing illegitimate content in a container comprising steps of:

obtaining each of measured gamma-ray data and measured neutron data from said container; and

comparing each of said measured gamma-ray data and said measured neutron data to a respective one of expected gamma-ray data and expected neutron data wherein an anomaly between said measured gamma-ray and neutron data and said expected gamma-ray and neutron data is an indicum of the presence of said material shielding said content.

2. A method as set forth in claim 1 wherein said expected gamma-ray and neutron data is background gamma-ray and neutron data.

3. A method as set forth in claim 2 wherein said background gamma-ray data and said background neutron data are respectively inspection day background gamma-ray data and inspection day background neutron data.

4. A method as set forth in claim 3 wherein said inspection day background gamma-ray data and said inspection day background neutron data are constituents of stored inspection day background fingerprints obtained for said container.

5. A method as set forth in claim 3 wherein said anomaly exists when said measured gamma-ray data is substantially less than said inspection day background gamma-ray data and said measured neutron data is substantially greater than inspection day background neutron data.

6. A method as set forth in claim 2 wherein said anomaly exists when said measured gamma-ray data substantially decreases from said expected gamma-ray data and said measured neutron data substantially increases from said background neutron data.

7. A method as set forth in claim 1 wherein said gamma-ray data and said neutron data are a selected respective one of a count of said gamma-ray emissions and said neutron emissions and an energy of said gamma-ray emissions and said neutron emissions.

8. A method as set forth in claim 1 wherein each of said measured gamma-ray data, said measured neutron data, said expected gamma-ray data and said expected neutron data is digitized data.

9. A method as set forth in claim 1 wherein said obtaining step is performed while said container is engaged by a hoist attachment, said hoist attachment including a gamma-ray detector and a neutron detector arranged proximal to said container to develop said measured gamma-ray data and said measured neutron data from detected gamma-ray emissions and neutron emissions emanating from said container when said container is engaged by said hoist attachment.

10. A method as set forth in claim 9 wherein said hoist attachment further includes a housing in which said gamma-ray detector and said neutron detector are disposed, said housing isolating said gamma-ray detector and said neutron detector from mechanical shock induced in said hoist attachment.

11. A method as set forth in claim 10 wherein said hoist attachment further includes an analyzer disposed in said housing to digitize each of said measured gamma-ray data and said measured neutron data.

12. A method as set forth in claim 1 further comprising the step of returning a status to signal said indicum.

13. A method as set forth in claim 1 wherein said measured gamma-ray and measured neutron data being substantially commensurate with said expected gamma-ray and said expected neutron data is an indicum of the presence of legitimate content in said container.

14. A computer readable medium containing executable code operable to detect the presence of radiation shielding material concealing illegitimate content in a container, said code implementing procedures of:

obtaining each of measured gamma-ray data and measured neutron data from said container; and

comparing each of said measured gamma-ray data and said measured neutron data to a respective one of expected gamma-ray data and expected neutron data wherein an anomaly between said measured gamma-ray and neutron data and said expected gamma-ray and neutron data is an indicum of the presence of said material shielding said content.

15. A computer readable medium as set forth in claim 14 wherein said expected gamma-ray and neutron data is background gamma-ray and neutron data.

16. A computer readable medium as set forth in claim 15 wherein said background gamma-ray data and said background neutron data are respectively inspection day background gamma-ray data and inspection day background neutron data.

17. A computer readable medium as set forth in claim 16 wherein said inspection day background gamma-ray data and said inspection day background neutron data are constituents of stored inspection day background fingerprints obtained for said container.

18. A computer readable medium as set forth in claim 16 wherein said anomaly exists when said measured gamma-ray data is substantially less than said inspection day background gamma-ray data and said measured neutron data is substantially greater than inspection day background neutron data.

19. A computer readable medium as set forth in claim 15 wherein said anomaly exists when said measured gamma-ray data substantially decreases from said expected gamma-ray data and said measured neutron data substantially increases from said background neutron data.

20. A computer readable medium as set forth in claim 14 wherein said gamma-ray data and said neutron data are a selected respective one of a count of said gamma-ray emissions and said neutron emissions and an energy of said gamma-ray emissions and said neutron emissions.

21. A computer readable medium as set forth in claim 14 wherein each of said measured gamma-ray data, said measured neutron data, said expected gamma-ray data and said expected neutron data is digitized data.

22. A computer readable medium as set forth in claim 14 wherein said obtaining step is performed while said container is engaged by a hoist attachment, said hoist attachment including a gamma-ray detector and a neutron detector arranged proximal to said container to develop said measured gamma-ray data and said measured neutron data from detected gamma-ray emissions and neutron emissions emanating from said container when said container is engaged by said hoist attachment.

23. A computer readable medium as set forth in claim 22 wherein said hoist attachment further includes a housing in which said gamma-ray detector and said neutron detector are disposed, said housing isolating said gamma-ray detector and said neutron detector from mechanical shock induced in said hoist attachment.

24. A computer readable medium as set forth in claim 23 wherein said hoist attachment further includes an analyzer disposed in said housing to digitize each of said measured gamma-ray data and said measured neutron data.

25. A computer readable medium as set forth in claim 14 further comprising the step of returning a status to signal said indicum.

26. A computer readable medium as set forth in claim 14 wherein said measured gamma-ray and measured neutron data being substantially commensurate with said expected gamma-ray and said expected neutron data is an indicum of the presence of legitimate content in said container.

27. An apparatus to determine the presence of radiation shielding material concealing illegitimate content in a container comprising:

a gamma-ray detector and a neutron detector respectively operable to obtain each of measured gamma-ray data and measured neutron data from said container; and

a computer operable to compare each of said measured gamma-ray data and said measured neutron data to a respective one of expected gamma-ray data and expected neutron data wherein an anomaly between said measured gamma-ray and neutron data and said expected gamma-ray and neutron data is an indicum of the presence of said material shielding said content.

28. An apparatus as set forth in claim 27 wherein said expected gamma-ray and neutron data is background gamma-ray and neutron data.

29. An apparatus as set forth in claim 28 wherein said background gamma-ray data and said background neutron data are respectively inspection day background gamma-ray data and inspection day background neutron data.

30. An apparatus as set forth in claim 29 further comprising an inspection day background fingerprint database containing inspection day background fingerprints obtained for said container, said inspection day background gamma-ray data and said inspection day background neutron data being constituents of stored inspection day background fingerprints.

31. An apparatus as set forth in claim 29 wherein said anomaly exists when said measured gamma-ray data is substantially less than said inspection day background gamma-ray data and said measured neutron data is substantially greater than inspection day background neutron data.

32. An apparatus as set forth in claim 28 wherein said anomaly exists when said measured gamma-ray data substantially decreases from said expected gamma-ray data and said measured neutron data substantially increases from said background neutron data.

33. A method as set forth in claim 27 wherein said gamma-ray data and said neutron data are a selected respective one of a count of said gamma-ray emissions and said neutron emissions and an energy of said gamma-ray emissions and said neutron emissions.

34. An apparatus as set forth in claim 27 wherein each of said measured gamma-ray data, said measured neutron data, said expected gamma-ray data and said expected neutron data is digitized data.

35. An apparatus as set forth in claim 27 wherein said container is engaged by a hoist attachment, said a gamma-ray detector and a neutron detector being carried by said hoist attachment proximal to said container to develop said measured gamma-ray data and said measured neutron data from detected gamma-ray emissions and neutron emissions emanating from said container when said container is engaged by said hoist attachment.

36. An apparatus as set forth in claim 35 further comprising a housing in which said gamma-ray detector and said neutron detector are disposed, said housing being carried by said hoist attachment and isolated therefrom to isolate said gamma-ray detector and said neutron detector from mechanical shock induced in said hoist attachment.

37. An apparatus as set forth in claim 36 further comprising an analyzer disposed in said housing to digitize each of said measured gamma-ray data and said measured neutron data.

38. An apparatus as set forth in claim 27 wherein said computer is further operative to return a status to signal said indicum.

39. An apparatus as set forth in claim 27 wherein said measured gamma-ray and measured neutron data being substantially commensurate with said expected gamma-ray and said expected neutron data is an indicum of the presence of legitimate content in said container.

40. A method of inspecting a container for a presence of illegitimate content comprising steps of:

obtaining each of measured gamma-ray data and measured neutron data from said container to obtain a respective one of a container gamma-ray fingerprint and a container neutron fingerprint for said container;

comparing each of said container gamma-ray fingerprint and said container neutron fingerprint to each one of a plurality of pairs of a weapon gamma ray fingerprint and a weapon neutron fingerprint wherein a heuristic match between said container gamma-ray fingerprint and said container neutron fingerprint and one of said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint is an indicum of said presence of illegitimate content; and

comparing, in the event said indicum of said presence of illegitimate content is null, each of said measured gamma-ray data and said measured neutron data to a respective one of expected gamma-ray data and expected neutron data wherein an anomaly between said measured gamma-ray and neutron data and said expected gamma-ray and neutron data is an indicum of the presence of radiation shielding material concealing said illegitimate content.

41. A method as set forth in claim 40 further comprising the step of constructing a weapon fingerprint database, said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint being stored in said weapon fingerprint database.

42. A method as set forth in claim 41 wherein for each one of said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint said constructing step includes the steps of:

developing gamma ray data and neutron data from a test container containing a sample of a known radioactive material;

digitizing said data to develop said one of said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint; and

storing said one of said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint in said weapons fingerprint database.

43. A method as set forth in claim 42 wherein said one of said pairs is cross-referenced to said sample in said weapon fingerprint database.

44. A method as set forth in claim 42 further comprising the step of normalizing said one of said pairs of said weapon gamma ray fingerprint and said weapon neutron fingerprint.

45. A method as set forth in claim 44 wherein said normalizing step includes the steps of:

developing gamma ray data and neutron data from an empty test container;

digitizing said data from said empty container to develop a background gamma-ray fingerprint and a background neutron fingerprint; and

subtracting said background gamma-ray fingerprint and said background neutron fingerprint from said weapon gamma ray fingerprint and said weapon neutron fingerprint in each one of said pairs.

46. A method as set forth in claim 40 further comprising the step of comparing each of said container gamma-ray fingerprint and said container neutron fingerprint respectively to a purported gamma-ray fingerprint and a purported neutron fingerprint wherein a heuristic match between said container gamma-ray fingerprint and said container neutron fingerprint and said purported gamma-ray fingerprint and said purported neutron fingerprint is an indicum that said container contains legitimate contents, said measured data comparing step being performed in the event said indicum of said presence of legitimate content is null.

47. A method as set forth in claim 46 further comprising the steps of:

querying a manifest database with a container ID of said container to obtain each commodity ID of each item purported to be in said container; and

querying a manifest fingerprint database containing a gamma-ray fingerprint and a neutron fingerprint for each commodity ID, said purported gamma-ray fingerprint and said purported neutron fingerprint being combined from each of said gamma-ray fingerprint and said neutron fingerprint for each commodity ID.

48. A method as set forth in claim 47 wherein said manifest database is a manifest electronic file maintained by customs authorities, a terminal operator or a transport company.

49. A method as set forth in claim 47 further comprising the step of constructing said manifest fingerprint database.

50. A method as set forth in claim 49 wherein for each commodity ID said constructing step includes the steps of:

developing gamma ray data and neutron data from a test container containing an item of known legitimate contents;

digitizing said data to develop said manifest gamma ray fingerprint and said manifest neutron fingerprint for said item; and

storing said manifest gamma ray fingerprint and said manifest neutron fingerprint in said manifest fingerprint database.

51. A method as set forth in claim 50 wherein said manifest gamma ray fingerprint and said manifest neutron fingerprint is cross-referenced to said commodity ID for said item.

52. A method as set forth in claim 50 further comprising the step of normalizing said manifest gamma ray fingerprint and said manifest neutron fingerprint.

53. A method as set forth in claim 52 wherein said normalizing step includes the steps of:

developing gamma ray data and neutron data from an empty test container;

digitizing said data from said empty container to develop a background gamma-ray fingerprint and a background neutron fingerprint; and

subtracting said background gamma-ray fingerprint and said background neutron fingerprint from said manifest gamma ray fingerprint and said manifest neutron fingerprint.

54. A method as set forth in claim 40 further comprising normalizing said container gamma-ray fingerprint and said container neutron fingerprint to develop respectively a normalized container gamma-ray fingerprint and a normalized container neutron fingerprint.

55. A method as set forth in claim 54 wherein said normalizing step includes the steps of:

developing gamma ray data and neutron data from an empty test container on the day said container is to be inspected;

digitizing said data from said empty container to develop an inspection day background gamma-ray fingerprint and an inspection day background neutron fingerprint; and

subtracting said inspection day background gamma-ray fingerprint and said inspection day background neutron fingerprint from said container gamma ray fingerprint and said container neutron fingerprint.