8404474
Stereo Matching and 3-D Reconstruction for Optic Disk Images
3-D visualization of optic disk surface is very useful in diagnosis and observation of some eye diseases. It helps physicians in understanding and interpreting the stereo disc photographs(SDPs) which is widely used in clinical situations. This paper proposed a segment-based stereo matching algorithm, which represents the fundus structure as a Bayesian network and applies belief propagation(BP) to solve the maximum a posterior(MAX) estimation. Only ground control pixels(GCPs) of the BP results are retrieved and the dense disparity map is obtained by cubic interpolation and Gaussian blurring to ensure smoothness. The resulted 3-D retinal surface shows our approach is promising.
46639537
Hierarchical Stereo Matching: From Foreground to Background
2688754
A method for evaluating upper bound of simultaneous switching gates using circuit partition
This paper presents a method for evaluating an upper bound of simultaneous switching gates in combinational circuits. In this method, the original circuit is partitioned into subcircuits, and the upper bound is approximately computed as the sum of maximum switching gates for all subcircuits. In order to increase the accuracy, we adopted an evaluation function that takes account of both the interconnections among subcircuits and the number of generated subcircuits. Experimental results for ISCAS circuits show that the method efficiently evaluates the upper bounds of switching gates.
2257586
Applying neighborhood consistency for fast clustering and kernel density estimation
Nearest neighborhood consistency is an important concept in statistical pattern recognition, which underlies the well-known k-nearest neighbor method. In this paper, we combine this idea with kernel density estimation based clustering, and derive the fast mean shift algorithm (FMS). FMS greatly reduces the complexity of feature space analysis, resulting satisfactory precision of classification. More importantly, we show that with FMS algorithm, we are in fact relying on a conceptually novel approach of density estimation, the fast kernel density estimation (FKDE) for clustering. The FKDE combines smooth and non-smooth estimators and thus inherits advantages from both. Asymptotic analysis reveals the approximation of the FKDE to standard kernel density estimator. Data clustering and image segmentation experiments demonstrate the efficiency of FMS.
31414473
Improved Learning Algorithm Based on Generalized SOM for Dynamic Non-linear System
This paper proposes an improved learning algorithm based on generalized SOM for dynamical non-linear system identification. To improve the convergent speed and the accuracy of SOM algorithm, we propose the improved self-organizing algorithm, which, at first, applies the multiple local models instead of the global model, and secondly, adjusts the weights of the computing output layers along with the weights of the competing neurons layer during the training process. We prove that the improved algorithm is convergent if the network has suitable initial weights and small positive real parameters. The simulation results using our improved generalized SOM show an improvement for non-linear system compared to traditional neural network control systems.
7532408
Simplifying Mixture Models Through Function Approximation
The finite mixture model is widely used in various statistical learning problems. However, the model obtained may contain a large number of components, making it inefficient in practical applications. In this paper, we propose to simplify the mixture model by minimizing an upper bound of the approximation error between the original and the simplified model, under the use of the L 2 distance measure. This is achieved by first grouping similar components together and then performing local fitting through function approximation. The simplified model obtained can then be used as a replacement of the original model to speed up various algorithms involving mixture models during training (e.g., Bayesian filtering, belief propagation) and testing [e.g., kernel density estimation, support vector machine (SVM) testing]. Encouraging results are observed in the experiments on density estimation, clustering-based image segmentation, and simplification of SVM decision functions.
14385690
A New Least Squares Subspace Projection Approach to Unmix Hyperspectral Data
Linearly constrained discriminant analysis (LCDA) and orthogonal subspace projection (OSP) are both explored in hyperspectral image classification and have shown promise in signature detection, discrimination and classification. However, the two subspace projection approaches cannot directly estimate the signature abundance. The OSP has been extended by a least squares orthogonal subspace projection (LSOSP) to estimate the signature abundance while LCDA has not. The solution of LCDA turns out to be a constrained version of OSP implemented with a data whitening process and the means of samples as signatures. Due to this fact, following the same idea for extending OSP to LSOSP, in this paper, a modified linearly constrained discriminant analysis (MLCDA) is proposed for unmixing hyperspectral data, which can directly estimate the signature abundance. Experiment results obtained from both artificial simulated and practical remote sensing data demonstrate that the MLCDA algorithm performs better than least squares method and the LSOSP.