Heuristic Method for Photo-detectors Localization over Continuous Crystal Scintillation Cameras

The construction process of large scintillation cameras with continuous crystals is a complex problem affected by multiple variables, from the physical construction of the scintillation crystal to the dispersion in the sensibility of photomultiplier tubes. The selection of these variables have a strong impact on the final performance of the scintillation camera. A new method to select photomultiplier is presented in this paper, regarding its gain, making use of k-means clustering and genetic algorithms. The proposed algorithm was tested and applied in the construction of six scintillation cameras for the Argentinean positron emission tomogaph prototype (AR-PET), a problem with more than 10+600 possible configurations. The resulting configuration of the scintillation cameras reduced the software-freecalibration FWHM of the camera from 20% to 15% average.

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An Improved Method of Renography Using the Split Crystal Scintillation Camera

The Journal of Urology ◽

10.1016/s0022-5347(17)62770-8 ◽

1968 ◽

Vol 99 (6) ◽

pp. 681-687 ◽

Cited By ~ 8

Author(s):

John C. Harbert ◽

William L. Ashburn ◽

Jack D. Davidson

Keyword(s):

Scintillation Camera ◽

Improved Method ◽

Crystal Scintillation

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Photo-Detectors for Time of Flight Positron Emission Tomography (ToF-PET)

Sensors ◽

10.3390/s101110484 ◽

2010 ◽

Vol 10 (11) ◽

pp. 10484-10505 ◽

Cited By ~ 53

Author(s):

Virginia Ch. Spanoudaki ◽

Craig S. Levin

Keyword(s):

Positron Emission Tomography ◽

Time Of Flight ◽

Emission Tomography ◽

Positron Emission ◽

Photo Detectors ◽

Tof Pet

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Energy and spatial resolution for a continuous scintillation crystal - interface - continuous scintillation crystal system in Positron Emission Tomography(PET)

2009 IEEE Nuclear Science Symposium Conference Record (NSS/MIC) ◽

10.1109/nssmic.2009.5401700 ◽

2009 ◽

Author(s):

M. Carles ◽

A. Ros-Garcia ◽

Ch. W. Lerche ◽

F. Sanchez ◽

A. Sebastia ◽

...

Keyword(s):

Positron Emission Tomography ◽

Spatial Resolution ◽

Emission Tomography ◽

Scintillation Crystal ◽

Crystal System ◽

Positron Emission ◽

Crystal Interface

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Use of digirad 2020tc ImagerTM, a multi-crystal scintillation camera with solid-state detectors in one case for the imaging of autografts of parathyroid glands

Annals of Nuclear Medicine ◽

10.1007/bf02988508 ◽

2001 ◽

Vol 15 (6) ◽

pp. 533-536 ◽

Cited By ~ 5

Author(s):

Nobuyoshi Fukumitsu ◽

Daisuke Tsuchida ◽

Shigeyuki Ogi ◽

Mayuki Uchiyama ◽

Yutaka Mori ◽

...

Keyword(s):

Solid State ◽

Parathyroid Glands ◽

Scintillation Camera ◽

Solid State Detectors ◽

Crystal Scintillation

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Selected Warehousing Practices in Bulgarian Trade and Manufacturing Enterprises

Economic and social alternatives ◽

10.37075/isa.2021.4.06 ◽

2021 ◽

Vol 27 (4) ◽

pp. 72-85

Keyword(s):

Management Practices ◽

Service Providers ◽

Human Resources Management ◽

Complex Problem ◽

Theory And Practice ◽

Strong Impact ◽

Material Flows ◽

Manufacturing Enterprises ◽

Modern Business ◽

Logistics Activity

Warehousing is an essential logistics activity that has a particularly strong impact on the movement of material flows in the supply chain. That is why in modern business concepts warehouses are an important part of efficient logistics systems. Warehousing management is a complex problem that requires economics and technical knowledge. Based on this, a number of related specifics for the management of these systems could be found in theory and practice. The article presents the results of a survey focused on Bulgarian trade and manufacturing enterprises and reveals some of the warehousing management practices. The scope of the study does not include logistics service providers. Several problems that have an important role in warehousing management are considered as an article focus, such as the characteristics of material flows, main challenges for warehousing systems, degree of integration of warehousing processes, application of quality management and controlling practices, human resources management, sustainable storage practices and usage of information systems and technologies in warehousing. Based on the research data, several conclusions are defined about the practices in warehousing in Bulgaria.

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Influence of the scintillation crystal option on the detector response of pet devices

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1401040a ◽

2014 ◽

Vol 29 (1) ◽

pp. 40-45

Author(s):

Vojislav Antic ◽

Koviljka Stankovic ◽

Milos Vujisic ◽

Predrag Osmokrovic

Keyword(s):

Positron Emission Tomography ◽

Medical Image ◽

Radioactive Tracer ◽

The Body ◽

Emission Tomography ◽

Detector Response ◽

Biochemical Activity ◽

Scintillation Crystal ◽

Positron Emission ◽

Scintillation Decay Time

Positron emission tomography is a technology that provides unique and exquisite possibilities in functional diagnostics, in the sense that it is the most efficient and most reliable method for obtaining information about biochemical activity and cellular metabolism in the body, by determining exact localization and performing semi-quantitative assessment of the distribution of a radioactive tracer. This paper compares the characteristics of recently introduced lutetium based crystals to those of conventionally used bismuth-ortho-germanate scintillators; both options are used as scintillation detectors within the positron emission tomography systems. Energy resolution and scintillation decay time of lutetium based crystals and bis-muth-ortho-germanate crystals was experimentally tested. Main scintillation detector parameters which affect the resulting detector response are considered and analyzed, since they serve as the basis for a positron emission tomography medical image.

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New a-Si:H Photo-Detectors for Long-Term Charge Storage

MRS Proceedings ◽

10.1557/proc-297-1023 ◽

1993 ◽

Vol 297 ◽

Cited By ~ 3

Author(s):

H. Lee ◽

G. Cho ◽

J.S. Drewery ◽

W.S. Hong ◽

T. Jing ◽

...

Keyword(s):

Amorphous Silicon ◽

Storage Time ◽

Metal Layer ◽

Incident Light ◽

Scintillation Camera ◽

Central Metal ◽

New Device ◽

External Bias ◽

Photo Detectors

Using the high light absorption properties of amorphous silicon, we developed a new device configuration that can detect photons and store the induced charges for relatively long time. This device, coupled to a scintillator such as CsI(Tl) in an array form, could be used as a scintillation camera, or for long-term photo-detection such as radionuclide labeled chromatography. The detector has a simple sandwich structure consisting of a scintillator followed by a top metal layer, p-i-n layers of hydrogenated amorphous silicon (a-Si:H), a second metal layer, a thin insulating layer and a bottom metal layer. The electron-hole pairs generated in the i-layer by the interaction with the incident light will be separated by the imposed electric field and be stored in the central metal-insulator interface. Readout will be done by switching the external bias to ground after the storage time, which depends on the needs for the specific application. Prototype devices were fabricated and tested. The performances of the devices were analyzed in connection with the storage time and the background signal produced by the thermally generated charges.

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