Dynamic positron emission tomography (PET) is widely used to measure variations of radiopharmaceuticals within the organs over time. However, conventional reconstruction algorithm can produce a noisy reconstruction if...
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ISBN:
(纸本)9781467364560
Dynamic positron emission tomography (PET) is widely used to measure variations of radiopharmaceuticals within the organs over time. However, conventional reconstruction algorithm can produce a noisy reconstruction if there are not sufficient photon counts. Hence, the main goal of this paper is to develop a novel spatio-temporal regularization approach that exploits inherent similarities within intra- and inter-frames to overcome the limitation. One of the main contributions of this paper is to demonstrate that such correlations can be exploited using a low rank constraint of overlapping similarity blocks. The resulting optimization framework is, however, non-smooth and non Lipschitz due to the low-rank penalty terms and Poisson log-likelihood. Therefore, we propose a novel globally convergent optimization method using the concave-convex procedure (CCCP) by exploiting Legendre-Fenchel transform, which overcomes the memory and computational limitations. We confirm that the proposed algorithm can provide significantly improved image quality and extract accurate kinetic parameters.
In view of the wide use of the “Gaussian distribution hypothesis of noise” in geophysical inversion problems, we study the non-Gaussian distribution characteristics of the noise in pre-stack seismic data. Upon this ...
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In view of the wide use of the “Gaussian distribution hypothesis of noise” in geophysical inversion problems, we study the non-Gaussian distribution characteristics of the noise in pre-stack seismic data. Upon this analysis, the concept of non-Gaussian inversion of pre-stack three-term inversion is put forward, in which the mixed-norm is proposed for suppressing both the Gaussian and non-Gaussian noises. In view of the non-derivable feature of the objective function, the Powell algorithm is used to solve the objective function. Model test and real seismic data inversion results show the correctness and reliability of the algorithm.
The principle of orthogonality using orthogonal projection (OP) is the key concept to develop mean squared error estimation theory in signalprocessing and communications. It has also found its way in a wide variety o...
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Dual-satellite geolocation system is an effective passive location technique. This method can locate a stationary emitter on Earth by using time and frequency differences of arrival (TDOA/FDOA).In this paper, the rank...
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Membrane computing is an emergent branch of natural computing, which is inspired by the structure and the functioning of living cells, as well as the organization of cells in tissues, organs, and other higher order st...
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Membrane computing is an emergent branch of natural computing, which is inspired by the structure and the functioning of living cells, as well as the organization of cells in tissues, organs, and other higher order structures. Tissue P systems are a class of the most investigated computing mod- els in the framework of membrane computing, especially in the aspect of efficiency. To generate an exponential resource in a polynomial time, cell separation is incorporated into such systems, thus obtaining so called tissue P systems with cell separation. In this work, we exploit the computational efficiency of this model and construct a uniform family of such tissue P systems for solving the independent set problem, a well-known NP-complete problem, by which an efficient so- lution can be obtained in polynomial time.
A weight constrained total least-square (WCTLS) is developed for source localization by using time difference of arrival (TDOA) measurements. The WCTLS algorithm not only exploits the structure information of the meas...
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The theory of compressive sensing (CS) enables the reconstruction of a sparse signal from highly compressed data. However, in many applications, we are ultimately interested in information retrieval rather than signal...
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The theory of compressive sensing (CS) enables the reconstruction of a sparse signal from highly compressed data. However, in many applications, we are ultimately interested in information retrieval rather than signal reconstruction. In this paper, we study the problem of multi-objects classification in compressive sensing systems. Theoretical error bounds are derived based on the analysis of classical compressive classification. The optimal projection matrix design problem is studied and an algorithm is derived to solve the corresponding problem. Application in the identification of license plate numbers is considered and simulation results show that the projection measurement obtained using the proposed algorithm significantly improve the classification performance in terms of classification error rate.
The collective dynamics of a randomly connected neuronal network motivated by the anatomy of a mammalian cortex based on a simple model are *** simple model can not only reproduce the rich behaviors of biological neur...
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The collective dynamics of a randomly connected neuronal network motivated by the anatomy of a mammalian cortex based on a simple model are *** simple model can not only reproduce the rich behaviors of biological neurons but also has only two equations and one nonlinear *** varying some key parameters,such as the connection weights of neurons,the external current injection and the noise of intensity,this neuronal network will exhibit various collective *** is demonstrated that the synchronization status of the neuronal network has a strong relationship with the key parameters and the external current has more influence on the spiking of inhibitory neurons than that of excitatory *** results may be instructive in understanding the collective dynamics of a mammalian cortex.
The non-ideal conditions of real-world detection environments, such as beam-pattern mismatch, non-ideal sensor geometry, receiver channel imbalance and clutter heterogeneity, can preclude the performance described in ...
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This paper presents a new combination scheme for reducing the number of focal elements to manipulate in order to reduce the complexity of the combination process in the multiclass framework. The basic idea consists in...
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ISBN:
(纸本)9781479902842
This paper presents a new combination scheme for reducing the number of focal elements to manipulate in order to reduce the complexity of the combination process in the multiclass framework. The basic idea consists in using of p sources of information involved in the global scheme providing p kinds of complementary information to feed each set of p one class support vector machine classifiers independently of each other, which are designed for detecting the outliers of the same target class, then, the outputs issued from this set of classifiers are combined through the plausible and paradoxical reasoning theory for each target class. The main objective of this approach is to render calibrated outputs even when less complementary responses are encountered. An inspired version of Appriou's model for estimating the generalized basic belief assignments is presented in this paper. The proposed methodology allows decomposing a n-class problem into a series of n-combination, while providing n-calibrated outputs into the multi-class framework. The effectiveness of the proposed combination scheme with proportional conflict redistribution algorithm is validated on digit recognition application and is compared with existing statistical, learning, and evidence theory based combination algorithms.
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