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In this paper, we analyze the performances of the Cell Averaging based on Lookup Tables (CA-LT) detector considering distributed targets embedded in Pareto distributed clutter. Assuming that the clutter parameters are not a priori known, the detector's structure is associated to an estimation approach that estimates the clutter parameters. The latter are used to select the suitable threshold factor...
Anthropogenic underwater sound is now recognized as a world-wide problem. Shipping, seismic surveys and pile driving, among some other human activities, have shown a broad range of negative effects in a variety of species. It is thus important to control, register and characterize these activities in order to establish policies that mitigate its effects. For this purpose, automatic detectors of the...
X-ray pulsar-based navigation method is a promising autonomous navigation method. The research has been done for nearly 30 years. Several key techniques about this method are the research hotspots now. One of the key techniques is estimation of the time of arrival (TOA) in pulsar's signal processing. The precision of the TOA would affect the precision of X-ray pulsar-based navigation. Using Monte...
The development of low complexity, high performance spatial-multiplexing MIMO detectors continues to be an important area of research capable of increasing the spectral efficiency and capacity of wireless networks. The Markov Chain Monte Carlo (MCMC) detector has shown promise as a high performance method with low complexity growth. We present a solution to the high SNR stalling problems of previous...
Bowtie filter, as a beam shaping attenuator placed between X-ray source and scanned object in computed tomography system, can effectively reduce radiation dose. In addition, the bowtie filter is expected to be able to compress the dynamic range which could limit the application of some detectors. In this paper, we propose a methodology for dynamic bowtie which can balance the photon flux on a detector...
In this manuscipt, detection of antipodal and biorthogonal chirp signals in Laplacian noise has been studied. In this context, detector test statistics and detection performances based on Neyman-Pearson and Bayesian approaches have been derived analytically and confirmed numerically through Monte Carlo simulations. Results have shown that both of the approaches give the same detector with different...
The purpose of this paper is to derive new asymptotic properties of the robust adaptive normalized matched filter (ANMF). More precisely, the ANMF built with Tyler estimator (TyE-ANMF) is analyzed under the framework of complex elliptically symmetric (CES) distributions. We show that the distribution of TyE-ANMF can be accurately approximated by the well-known distribution of the ANMF built with the...
The α-η-μ distribution is a generalized distribution which models the fading statistics to a sufficient degree of accuracy in practice. This distribution includes the well-studied models such as Rice, Rayleigh, Nakagami-m, Weibull, η-μ and α-μ distributions as special cases. We study the problem of energy-based spectrum sensing over the α-η-μ fading channel, following a Bayesian approach. We present...
Detection of particles from a far-field source is important in many applications, including optical communications, nuclear hazard detection, radioactivity and detection of cosmic particles. In this paper, we revisit the problem of detection of far-field particle sources using a cubical array. For the case when the source location is deterministic, assuming Poisson arrival of particles, we propose...
The performance of the learning-based detector depends much on its training dataset and decreases rapidly when it is tested on a new scene. The reason is that in the large variations between the source training dataset and target scene. To solve this problem, we propose a novel approach to automatically specialize a generic detector to specific scene by utilizing the sequential Monte Carlo filter...
Faster alternatives to a full, GEANT4-based simulation are being pursued within LHCb experiment. In this context the integration of the Delphes toolkit in the LHCb simulation framework is intended to provide a fully parameterized option. Delphes is a modular software designed to perform fast simulations by propagating stable particles using a parametric approach and providing reconstructed physical...
A detailed study of hadronic interactions is presented using data recorded with the highly granular CALICE silicon-tungsten electromagnetic calorimeter. The predictions of several Monte Carlo GEANT4 models are compared with experimental data, taken at FNAL in 2008. The contribution recaps results published in 2015 and a set of new results available since the beginning of 2016. The published results...
Publicly available Monte Carlo simulation packages for light transport in scintillator-based x-ray imaging detectors utilize a linear yield model. However, scintillators are known to be non-linear in the lower end of the energy range. Is this assumption reasonable for x-ray imaging simulations? We modified a freely available Monte Carlo package for modeling x-ray scintillators (MANTIS) to compare...
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...
Compact ring diameter PET systems suffer degradation in spatial resolution with increasing radial offset due to the parallax error caused by depth of interaction (DOI) effects. In this work, we study the problem of optimizing layer thicknesses for a detector that uses a dual-layer offset (DLO) scintillator array. In this design, a half-crystal offset exists between the crystals in the front and back...
Measuring system response matrix (SRM) by Monte Carlo method is time and resource consuming, even with high performance computer nodes. In this paper, we exploited symmetry properties available to drastically reduce the complexity in computing SRM of panel PET, which has two parallel panel detectors. By extending the original system and simulating 4 voxels every slice parallel to the PET detector,...
We are currently developing a dual-particle imager based on the rotational modulation collimator (RMC) technique employing Cs2LiYCl6:Ce (CLYC) detector. A symmetric mask design has been conventionally used for RMC, however, it has an intrinsic problem of not being able to distinguish two symmetric sources located with respect to the rotation axis. In the present study, we propose a new design of collimator...
A direct-conversion photon-counting detector has great potential in CT imaging and has been intensively studied in recently years. However, the optimization of the detector configuration based on clinically-relevant metrics is still lacking. In this study, we developed an optimization scheme for CZT-based photon-counting detector design. The spectral response functions characterizing different detector...
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...
CALICE collaboration is developing highly granular calorimeters for future high energy e+e- colliders. Using Particle Flow Algorithms for individual reconstruction of particles in the jets, they provide currently the best jet energy resolution. At high jet energies (typically above 70–100GeV in the proposed detectors), the jet particle showers start to overlap, and the resolution is determined by...
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