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The use of time-of-flight (TOF) information in positron emission tomography (PET) can significantly improve image quality. Many analytical expressions have been proposed to predict the variance of PET images. However, these methods become impractically time-consuming for TOF-PET. Our work is motivated by the goal of deriving a fast algorithm that can accurately predict image variance of TOF-PET. We...
A new time-delay estimation method based upon Cubic spline interpolation and Area bary center algorithm that is well suitable for determining the time-delay between two noisy band-limited signals is introduced. Unlike conventional correlation algorithm, the new approach has the ability to optimally estimate any non-integral sample delay only using Cubic spline interpolation and Area bary center algorithm...
This paper focuses research on prediction of network utilization for NCS (networked control system). The Two kind models of the network utilization are set up and discussed, which are AR (Auto-Regressive) model and ARMA (Auto-Regressive and Moving Average) model. The ARMA model of network utilization is proposed, which considers not only historical data of network utilization but also historical data...
This paper discusses the stochastic adaptive tracking problem with input quantization, where the unknown parameters are described as a Gauss-Markov process. Based on the analysis of the cautious control law under quantization, the innovations dual controller is proposed. The quantization errors of logarithmic quantizer introduce the excitation of parameter estimation and hence improve the total closed-loop...
This article investigates the cooperative H∞ filtering problem of multi-agent systems. The filter input consists of relative states among neighboring agents and the individual states of a few agents. A topology graph is applied to represent the communication links among agents. The filtering error system is composed of the original system state, filter system state and the estimation error of relative...
The modeling and health condition assessment for degradation process are crucial to the effective machine fault diagnosis and prognosis. They provide a potent tool for operators in decision-making by specifying the present machine state and estimating the remaining useful life (RUL). In this paper, the health conditions of degradation process are modeled as a hidden Markov chain and the physical outputs...
By analyzing information transmission in stable and unstable, open- and closed-loop linear continuous-time Gaussian systems, connections within the MMSE of causal estimation, mutual information rate, and the integral of a Popov function are discussed. Yovits' equality for scalar stable systems and Anderson's equality for scalar unstable systems concerning MMSE are extended to multivariable systems...
Aiming at tracking Closely Spaced Objects (CSO) from Infrared (IR) images, an algorithm is proposed based on probability hypothesis density (PHD) filter incorporating the signal amplitude feature. With the influence of the Point Spread Function (PSF) and limited resolution of IR Focal Plane Array (FPA) resulting in unresolved measurements problem, an image preprocessing is firstly used to detect and...
In order to study the spectral density properties of 900MHz radio signal, the time series theory is introduced into statistical analysis. By means of the statistical data from signal acquisition system, the spectral density analysis principle is introduced. Moreover, both the autoregressive (AR) spectral estimation and autoregressive moving average (ARMA) spectral estimation are taken into spectral...
Tracking of highly maneuvering targets with unknown behavior is a difficult problem in state estimation. This paper presents an adaptive interacting multiple model algorithm (IMM) utilizing adaptive turn rate models to track a maneuvering target. The turn rate is calculated at each step form the estimator of velocity and the radius of curvature of the trajectory of the target by using Least Square...
In early-warning radar surveillance environment, sequential procedures are preferred to detect the targets, for they promise a reduction in the time needed to take a decision. In this paper, a sequential detection algorithm is concerned and the interplay between the parameter dsnr and the system performance is mainly discussed. Numerical results have shown that sequential detector can lead a great...
An algorithm for reducing control points in NURBS surface skinning is proposed in this paper. We first give distance estimation between the input curves and the surface that has been removed a knot. Then we further reduce the control points in NURBS surface skinning within the given tolerance by utilizing the ldquoresidual distancerdquo. Furthermore, the algorithm is applied to simplify a NURBS surface...
Diffusion weighted magnetic resonance images allows one to infer white matter axon fiber orientations. Nowadays it is possible to estimate intra-voxel orientations at voxels where fibers cross or split. Though, the recovered orientations could be prone to error because of low signal to noise ratio, the complex fiber structure and/or reduced number of measurements. Spatial regularization can improve...
Real-time IP flow estimation has many potential applications in network management, monitoring, security, and traffic engineering. Existing techniques typically rely on flow definitions being constrained as subsets of the fields in packet headers. This makes flow-membership tests relatively inexpensive. In this paper, we consider a more general flow estimation problem that needs complex packet-payload...
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