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Super-resolution is a technique to reconstruct PET images at a higher spatial resolution than intrinsically available from the detector resolution. This is done through oversampling projection data by moving the detector ring or the patient bed at increments finer than the crystal pitch of the systems detectors, increasing the sampling frequency so that resolution may be recovered without aliasing...
A whole-body PET device is sometimes not suitable for brain studies because the achieved image resolution is typically not sufficient to investigate small size structures. Thus, a dedicated brain PET insert system with high performance would overcome such limitations. Moreover, these functional studies lack of anatomical information. It is shown elsewhere the convenience of simultaneously acquisition...
This paper introduces the detector simulation code DECIMO under development at the ESRF as well as some of its first applications. The code is organized as a modular Python package designed to simulate in a relatively easy and efficient way the complete detection chains of future X-ray detectors for synchrotron radiation experiments. The core of the simulation engine is based on Monte Carlo techniques...
The Energy-Resolved Neutron Imaging System RADEN, located at the J-PARC Materials and Life Science Experimental Facility in Japan, is the world's first dedicated high-intensity, short-pulsed neutron imaging beam line. To carry out energy-resolved neutron imging at RADEN, we use cutting-edge detector systems employing micropattern detectors and data acquisition systems based on Field Programmable Gate...
Performance of triple GEM prototypes has been evaluated by means of a muon beam at the H4 line of the SPS test area at CERN. The data from two planar prototypes have been reconstructed and analyzed offline with two clusterization methods: the center of gravity of the charge distribution and the micro Time Projection Chamber (μTPC). GEM prototype performance evaluation, performed with the analysis...
We designed a novel PET insert based on monolithic LYSO crystals. From our first evaluation, we can conclude that sub-millimeter detector spatial resolution, combined with accurate photon DOI determination, make it possible to acquire high resolution reconstructed images. This enables us to combine simultaneously high resolution and sensitivity PET with high field preclinical MRI to extract simultaneously...
This work reports on the characterization of TlBr detectors for use in nuclear medicine. Several different detectors have been used to assess the potential performance of the material. A 12 mm thick detector with a Frisch collar has been used to achieve an energy resolution of 3.5% at 511 keV and 2.3% at 662 keV. A 0.4 mm thick detector biased at 200 V has been operated in coincidence with an LSO...
XFCT is a promising new molecular imaging modality which is able to measure non-radioactive tracer molecules even in deep tissues. Unrestricted spatial resolution imaging with pencil beam x-ray excitation is possible but cannot be translated easily to clinical applications as scanning times are at least several hours. The spatial information accessed with Compton cameras (CCs) overcomes this drawback...
In recent years, a new generation of compact gamma cameras, based on monolithic scintillation crystals, has become increasingly widespread. The main advantages of small FoV gamma cameras with respect to the standard ones are high portability, low cost and low weight, allowing several clinical applications, from scintimammography to intraoperative tumor localization. In gamma cameras based on continuous...
Particle physics experiments often comprise tracking detectors with areas of up to a few square meters. If a spatial resolution of the order of 100μm and high-rate capability are required, Micro Pattern Gaseous Detectors (MPGD) are a cost-effective solution. However, the construction of large-area MPGDs is challenging, since tight fabrication tolerances have to be met to guarantee a stable and homogeneous...
Neutron imaging is widely used in scientific experiments and industrial applications. The neutron sensitive microchannel plate (nMCP) detector plays the role of registering penetrating neutrons and realizing high spatial resolution. The delay-line readout anode can achieve a high spatial resolution with an acceptable throughput. To optimize working parameters of the nMCP detector with the delay-line...
This paper describes methods to evaluate (and train) pixel classifiers when connected components is used as a post-processing step. In previous work the method was used to train a convolutional neural network for image segmentation and we provided pseudo-code for a disjoint-set based algorithm that efficiently calculates the Rand Error and its gradient. This paper describes the modifications we have...
This paper presents a multiple optodes arrangement method in functional near-infrared spectroscopy (fNIRS) for measuring the absolute concentrations of oxy-hemoglobin and deoxy-hemoglobin. To remove physiological noises, short/long-separation detectors are used in the spatially resolved spectroscopy approach. The proposed method is applied to measure the brain activity of five healthy male subjects...
Intra focal plane array(FPA) crosstalk is a primary development limiter of large, fine-pixel Geiger-mode avalanche photodiode (Gm-APD) arrays beyond 256×256 pixels. General analysis methods and results from MIT Lincoln Laboratory (MIT/LL) InP-based detector arrays will be presented.
Compressive THz imaging holds the potential for increased spatial resolution and imaging speed when only a small number of detectors is available. The understanding of illumination patterns is essential in determining the performance for a compressive imaging setup. The results presented here start with an evaluation of the performance of different mask types. Then the influence of deviations of the...
We present transmission properties of sub-wavelength apertures (<λ/100) and discuss their applications in the collection-mode near-field probe for use with terahertz time domain spectroscopy (THz-TDS). In the deep sub-wavelength regime, the aperture transmission contains mostly evanescent field components. We have characterized the transmission properties experimentally in the THz range for 2,...
Detection cof multiple scatterers for localizing the targets is one of the key issues in SAR tomography. Recently, a Generalized Likelihood Ratio Test based on support estimation (Sup-GLRT) [10] has been presented. This test exhibits a high computational complexity. In this paper a modified approach for reducing computational complexity (Fast-Sup-GLRT) is proposed. The prime objective is to analyze...
Positron emission tomography (PET) plays important roles in cancer diagnosis, neuroimaging and molecular imaging research; but potential points remain for which big improvements could be made, including spatial resolution, sensitivity and manufacturing costs. Therefore, research on next generation PET technologies remains a hot topic worldwide. Depth-of-interaction (DOI) measurement in the radiation...
Frequently, shields used for protection againstradiation contain some vacuum channels for passingcables and instruments for measurements. The neutrontransmission through these shields is an unavoidablephenomenon, so we have interested in this work to studyand discuss the effect of vacuum channels on neutrontransmission through shields [1]. We have considered aninfinite homogenous slab, with a fixed...
Remotely sensed hyperspectral imagery provides, at each pixel, a radiance spectrum with up to hundreds of distinct wavelength channels. This high-dimensional spectral information allows for pixel-level material discrimination, including applications to remotely detecting the presence of particular materials of interest within a scene. Target detection takes a spectrum (or multiple spectra) corresponding...
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