Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 4

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Wpływ dodatku przeciwutleniaczy do miazgi jabłkowej na zawartośc związków fenolowych w soku

100%

Gasik A. , Horubała A. , Kubicz E.

nr 05-06

Application of the compress sensing theory for improvement of the TOF resolution in a novel J-PET instrument

39%

Raczyński L. , Moskal P. , Kowalski P. , Wiślicki W. , Bednarski T. , Białas P. , Czerwiński E. , Gajos A. , Kapłon Ł. , Kochanowski A. , Korcyl G. , Kowal J. , Kozik T. , Krzemień W. , Kubicz E. , Niedźwiecki S. , Pałka M. , Rudy Z. , Salabura P. , Gupta-Sharma N. , Silarski M. , Słomski A. , Smyrski J. , Strzelecki A. , Wieczorek A. , Zieliński M. , Zoń N.

2016

tom Vol. 61, No. 1

35--39

Nowadays, in positron emission tomography (PET) systems, a time of fl ight (TOF) information is used to improve the image reconstruction process. In TOF-PET, fast detectors are able to measure the difference in the arrival time of the two gamma rays, with the precision enabling to shorten signifi cantly a range along the line-of-response (LOR) where the annihilation occurred. In the new concept, called J-PET scanner, gamma rays are detected in plastic scintillators. In a single strip of J-PET system, time values are obtained by probing signals in the amplitude domain. Owing to compressive sensing (CS) theory, information about the shape and amplitude of the signals is recovered. In this paper, we demonstrate that based on the acquired signals parameters, a better signal normalization may be provided in order to improve the TOF resolution. The procedure was tested using large sample of data registered by a dedicated detection setup enabling sampling of signals with 50-ps intervals. Experimental setup provided irradiation of a chosen position in the plastic scintillator strip with annihilation gamma quanta.

PALS investigations of free volumes thermal expansion of J-PET plastic scintillator synthesized in polystyrene matrix

39%

Wieczorek A. , Zgardzińska B. , Jasińska B. , Gorgol M. , Bednarski T. , Białas P. , Czerwiński E. , Gajos A. , Kamińska D. , Kapłon Ł. , Kochanowski A. , Korcyl G. , Kowalski P. , Kozik T. , Krzemień W. , Kubicz E. , Niedźwiecki S. , Pałka M. , Raczyński L. , Rudy Z. , Rundel O. , Sharma N. G. , Silarski M. , Silarski A. , Strzelecki A. , Wiślicki W. , Zieliński M. , Moskal P.

tom Vol. 60, No. 4, part 1

777--781

The polystyrene doped with 2,5-diphenyloxazole as a primary fluor and 2-(4-styrylphenyl)benzoxazole as a wavelength shifter prepared as a plastic scintillator was investigated using positronium probe in wide range of temperatures from 123 to 423 K. Three structural transitions at 260, 283, and 370 K were found in the material. In the o-Ps intensity dependence on temperature, the significant hysteresis is observed. Heated to 370 K, the material exhibits the o-Ps intensity variations in time.

Processing optimization with parallel computing for the J-PET scanner

33%

Krzemień W. , Bała M. , Bednarski T. , Białas P. , Czerwiński E. , Gajos A. , Gorgol M. , Jasińska B. , Kamińska D. , Kapłon Ł. , Korcyl G. , Kowalski P. , Kozik T. , Kubicz E. , Niedźwiecki S. , Pałka M. , Raczyński L. , Rudy Z. , Rundel O. , Sharma N. G. , Silarski M. , Słomski A. , Stola K. , Strzelecki A. , Trybek D. , Wieczorek A. , Wiślicki W. , Zieliński M. , Zgardzińska B. , Moskal P.

tom Vol. 60, No. 4, part 1

745--748

The Jagiellonian Positron Emission Tomograph (J-PET) collaboration is developing a prototype time of flight (TOF)-positron emission tomograph (PET) detector based on long polymer scintillators. This novel approach exploits the excellent time properties of the plastic scintillators, which permit very precise time measurements. The very fast fi eld programmable gate array (FPGA)-based front-end electronics and the data acquisition system, as well as low- and high-level reconstruction algorithms were specially developed to be used with the J-PET scanner. The TOF-PET data processing and reconstruction are time and resource demanding operations, especially in the case of a large acceptance detector that works in triggerless data acquisition mode. In this article, we discuss the parallel computing methods applied to optimize the data processing for the J-PET detector. We begin with general concepts of parallel computing and then we discuss several applications of those techniques in the J-PET data processing.