Sideslip angle,yaw rate,and vehicle velocity are essential for intelligent vehicle *** these vehicle states are not measured directly,some Kalman-based approaches have been developed to estimate these states using in-...
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Sideslip angle,yaw rate,and vehicle velocity are essential for intelligent vehicle *** these vehicle states are not measured directly,some Kalman-based approaches have been developed to estimate these states using in-vehicle ***,the existing studies seldom account for the influence of sensor data loss on estimation *** addition,the process and measurement noise change during the estimation process because of the various driving *** address these problems,an expectation-maximization robust extended Kalman filter(EMREKF)is ***,a robust extended Kalman filter(REKF)is developed to deal with the impact of missing ***,an improved expectationmaximization(EM)algorithm that considers data loss is presented to update the noise parameter of the REKF ***,the improved EM is fused with the REKF to form the EMREKF to estimate vehicle *** experimental results demonstrate that the EMREKF outperforms EKF,REKF,and maximum correntropy criterion EKF for various degrees of data loss and the proposed algorithm has a strong adaptive ability to different driving conditions.
Diversity combining of multiple time varying and correlated fading branches is investigated for direct-sequence spread-spectrum systems. The correlated branches are modeled and estimated jointly as a vector autoregres...
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Diversity combining of multiple time varying and correlated fading branches is investigated for direct-sequence spread-spectrum systems. The correlated branches are modeled and estimated jointly as a vector autoregressive (VAR) process. The joint estimation is shown to provide performance gain over separate estimation of the fading branches. The parameter matrices of the VAR model are estimated via the method of expectationmaximization (EM) with two algorithms. The first algorithm, using results from Kalman smoothing, provides a closed-form solution to the maximization problem in the. iterative EM procedure. However, the iterative EM-Kalman algorithm operates repeatedly on a batch of training data and results in large storage requirements and long processing delays. To overcome these disadvantages, a new algorithm with only forward-time recursions is proposed that approximates the iterative EM solution and efficiently adapts to slowly changing Doppler spreads. As a result, the new algorithm significantly reduces memory and training sequence requirements. Through computer simulations, a near ideal bit-error rate performance is found for both algorithms, and the efficacy of the new adaptive algorithm for channels with changing Doppler spreads is demonstrated.
In this paper, we propose a new non-stationary sources separation algorithm, which is referred to as autoregressive hidden Markov Gaussian process (AR-HMGP), in which the sources are non-stationary and temporally corr...
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In this paper, we propose a new non-stationary sources separation algorithm, which is referred to as autoregressive hidden Markov Gaussian process (AR-HMGP), in which the sources are non-stationary and temporally correlated. For the proposed algorithm, a generative model is employed to track the non-stationarity of the source where the temporal dependencies of sources are represented by autoregressive model (AR) and the distribution of the associated innovation process is described using non-stationary Gaussian process with hidden Markov model (HMM). We further explore the maximum likelihood (ML) method to estimate the parameters of the source model by using the expectation maximum (EM) algorithm. Our important findings reveal that (a) AR-HMGP algorithm outperforms the other three BSS algorithms for non-stationary sources separation, the instantaneous mixture system is also well corroborated with the effectiveness of our algorithm;(b) both independent and dependent non-stationary sources have been successfully separated;(c) the proposed algorithm is robust with respect to noise, while the other three algorithms are not. (C) 2017 Elsevier B.V. All rights reserved.
Hyperspectral excitation-resolved fluorescence tomography (HEFT) exploits the spectrally-dependent absorption properties of biological tissue for recovering the unknown three-dimensional (3D) fluorescent reporter dist...
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ISBN:
(纸本)9780819484338
Hyperspectral excitation-resolved fluorescence tomography (HEFT) exploits the spectrally-dependent absorption properties of biological tissue for recovering the unknown three-dimensional (3D) fluorescent reporter distribution inside tissue. Only a single light source with macro-illumination and wavelength-discrimination is required for the purpose of light emission stimulation and 3D image reconstruction. HEFT is built on fluorescent sources with a relatively broad spectral absorption profile (quantum dots) and a light propagation model for strongly absorbing tissue between wavelengths 560 nm and 660 nm (simplified spherical harmonics - SPN, - equations). The measured partial current of fluorescence light is cast into an algebraic system of equations, which is solved for the unknown quantum dot distribution with an expectation-maximization (EM) method. HEFT requires no source-detector multiplexing for 3D image reconstruction and, hence, offers a technologically simple design.
The proposed image reconstruction method exploits the spectrally dependent absorption properties of biological tissue and quantum dots for recovering the three-dimensional reporter distribution. Only a single light so...
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ISBN:
(纸本)9780819486851
The proposed image reconstruction method exploits the spectrally dependent absorption properties of biological tissue and quantum dots for recovering the three-dimensional reporter distribution. Only a single light source with macro-illumination needs to be used for the purpose of light emission stimulation and image reconstruction. The light propagation in strongly absorbing tissue is modeled with the simplified spherical harmonics (SPN) equations.
As the first step of the automatic image interpretation system, the automatic detection of the target must be accurate and fast. For synthetic aperture radar (SAR) images, CFAR detection algorithm is the most commonly...
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ISBN:
(纸本)9781450377201
As the first step of the automatic image interpretation system, the automatic detection of the target must be accurate and fast. For synthetic aperture radar (SAR) images, CFAR detection algorithm is the most commonly used target detection framework. In CFAR algorithm, the modeling of background clutter is very important, because the detection threshold is calculated based on this model. The Gumbel Mixed (GM) distribution model is proposed to model the background clutter, and the expected maximizationmethod (EM) is used to estimate the parameters of the model, and Newton iteration method is applied to obtain the detection threshold. The model is effective in modeling complex statistics, including but not limited to statistics involving heavy tail distribution. At the same time, os-cfar detection algorithm of ordered statistics based on the model was applied to detect ship targets in SAR images. The experimental data set was derived from public SAR images, and the effect was significantly improved compared with traditional methods.
Complementary information contained in each of the individual polarization mode of fully polarimetric PALSAR data is fused using expectationmaximization (EM) algorithm to improve information contents in the fused ima...
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ISBN:
(纸本)9781479964994
Complementary information contained in each of the individual polarization mode of fully polarimetric PALSAR data is fused using expectationmaximization (EM) algorithm to improve information contents in the fused image. A comparative analysis of supervised classifiers viz. parallelepiped and minimum distance is accomplished to assess the suitability of the particular classifier. It is also demonstrated that fusion indeed improves various figures of merit such as producer, user and overall accuracies.
The currently accepted method of modeling a-hat versus a eddy current data for probability of detection calculations involves time consuming and highly subjective operator intervention. We propose a new method which r...
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The currently accepted method of modeling a-hat versus a eddy current data for probability of detection calculations involves time consuming and highly subjective operator intervention. We propose a new method which removes all dependence on the operator and therefore enjoys 100% repeatability. We model the a-hat versus a response using local regression and calculate confidence bounds on probability of detection and A90 threshold curves using the bootstrap method. Censored data are modeled via the expectationmaximization algorithm and repeated measure correlations are fully estimated. We present results on four eddy current data sets to compare our new method with the current industry standard method.
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