State-of-the-art radiation detectors for medical imaging: Demands and trends

Author(s):  
Dimitra G. Darambara
2001 ◽  
Vol 72 (1) ◽  
pp. 67-72 ◽  
Author(s):  
D. Cavouras ◽  
I. Kandarakis ◽  
T. Maris ◽  
G.S. Panayiotakis ◽  
C.D. Nomicos

2009 ◽  
Vol 615-617 ◽  
pp. 845-848 ◽  
Author(s):  
Giuseppe Bertuccio ◽  
S. Caccia ◽  
Filippo Nava ◽  
Gaetano Foti ◽  
Donatella Puglisi ◽  
...  

The design and the experimental results of some prototypes of SiC X-ray detectors are presented. The devices have been manufactured on a 2’’ 4H-SiC wafer with 115 m thick undoped high purity epitaxial layer, which constitutes the detection’s active volume. Pad and pixel detectors based on Ni-Schottky junctions have been tested. The residual doping of the epi-layer was found to be extremely low, 3.7 x 1013 cm-3, allowing to achieve the highest detection efficiency and the lower specific capacitance of the detectors. At +22°C and in operating bias condition, the reverse current densities of the detector’s Schottky junctions have been measured to be between J=0.3 pA/cm2 and J=4 pA/cm2; these values are more than two orders of magnitude lower than those of state of the art silicon detectors. With such low leakage currents, the equivalent electronic noise of SiC pixel detectors is as low as 0.5 electrons r.m.s at room temperature, which represents a new state of the art in the scenario of semiconductor radiation detectors.


IEEE Access ◽  
2018 ◽  
Vol 6 ◽  
pp. 37023-37034 ◽  
Author(s):  
Lucie Leveque ◽  
Hilde Bosmans ◽  
Lesley Cockmartin ◽  
Hantao Liu

2009 ◽  
Author(s):  
A. H. Goldan ◽  
Bahman Hadji ◽  
K. S. Karim ◽  
G. DeCrescenzo ◽  
J. A. Rowlands ◽  
...  

1998 ◽  
Vol 67 (5) ◽  
pp. 521-525 ◽  
Author(s):  
I. Kandarakis ◽  
D. Cavouras ◽  
P. Prassopoulos ◽  
E. Kanellopoulos ◽  
C.D. Nomicos ◽  
...  

Author(s):  
Weijia Zhang

Multi-instance learning is a type of weakly supervised learning. It deals with tasks where the data is a set of bags and each bag is a set of instances. Only the bag labels are observed whereas the labels for the instances are unknown. An important advantage of multi-instance learning is that by representing objects as a bag of instances, it is able to preserve the inherent dependencies among parts of the objects. Unfortunately, most existing algorithms assume all instances to be identically and independently distributed, which violates real-world scenarios since the instances within a bag are rarely independent. In this work, we propose the Multi-Instance Variational Autoencoder (MIVAE) algorithm which explicitly models the dependencies among the instances for predicting both bag labels and instance labels. Experimental results on several multi-instance benchmarks and end-to-end medical imaging datasets demonstrate that MIVAE performs better than state-of-the-art algorithms for both instance label and bag label prediction tasks.


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