The matrix inversion lemma gives an explicit formula of the inverse of a positive-definite matrix A added to a block of dyads (represented as BBH) as follows: (A + BB H ) -1 = A -1 - A -1 B(I + B H A -1 B) -1 B...
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The matrix inversion lemma gives an explicit formula of the inverse of a positive-definite matrix A added to a block of dyads (represented as BBH) as follows: (A + BB H ) -1 = A -1 - A -1 B(I + B H A -1 B) -1 B H A -1 . It is well-known in the literature that this formula is very useful to develop a block-based recursive least-squares algorithm for the block-based recursive identification of linear systems or the design of adaptive filters. We extend this result to the case when the matrix A is singular, and present a matrix pseudo-inversion lemma. Based on this result, we propose a block-based adaptive multi-channel super-exponential algorithm (BAMSEA). We present simulation results for the performance of the block-based algorithm in order to show the usefulness of the matrix pseudo-inversion lemma.
A novel, computationally efficient and robust scheme for multiple initial point prediction has been proposed in this paper. A combination of spatial and temporal predictors has been used for initial motion vector pred...
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A novel, computationally efficient and robust scheme for multiple initial point prediction has been proposed in this paper. A combination of spatial and temporal predictors has been used for initial motion vector prediction, determination of magnitude and direction of motion and search pattern selection. Initially three predictors from the spatio-temporal neighbouring blocks are selected. If all these predictors point to the same quadrant then a simple search pattern based on the direction and magnitude of the final predicted motion vector is selected. However if the predictors belong to different quadrants then we start the search from multiple initial points to get a clear idea of the location of minimum point. In this case a small rood search pattern has been selected. The predictive search center is closer to the global minimum and thus decreases the effect of monotonic error surface assumption and its impact on the motion field. Its additional advantage is that it moves the search closer to the global minimum hence increases the computation speed. Further computational speed up has been obtained by considering the zero motion threshold for no motion blocks, and, specialized rood search pattern. The image quality measured in terms of PSNR also shows good results.
An algorithm of improved reduced spatial resolution video transcoding is proposed in this paper. An adaptive intra-refresh scheme is presented based on the relation between drift error and motion activity of inter-cod...
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An algorithm of improved reduced spatial resolution video transcoding is proposed in this paper. An adaptive intra-refresh scheme is presented based on the relation between drift error and motion activity of inter-coded blocks. The thresholds are dynamically adjusted according to the difference between the target bit rate and actual bit rate. This method can reduce the bit rate of intra coded frames while still maintaining error robustness and limiting temporal propagation of errors. Besides, a linear rate control strategy is also present. In order to reduce computational complexity, the rate-distortion function can be mapped into a linear function. The simulation results show that the buffer fullness tend to be stabilized and the PSNR of the reconstructed image is raised.
Automatic keyword extraction is one of the most important techniques in natural language processing. In this paper, features of complex networks composed of Chinese are studied. A novel automatic keyword extraction al...
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Automatic keyword extraction is one of the most important techniques in natural language processing. In this paper, features of complex networks composed of Chinese are studied. A novel automatic keyword extraction algorithm for Chinese document is proposed which is based on the features of the complex networks according to the small world structure in language networks and the theoretical achievements in complex networks. It extracts keyword based on the feature values of the word nodes in a documental language network. Experimental results show the proposed algorithm obtains higher average precision compared with the keyword extraction algorithm based on TFIDF.
It has been shown that CMOS imaging technology can be applied to Digital Autoradiography (AR) as a potential imaging alternative technology to using conventional film emulsion. In this work a thorough investigation on...
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It has been shown that CMOS imaging technology can be applied to Digital Autoradiography (AR) as a potential imaging alternative technology to using conventional film emulsion. In this work a thorough investigation on the performance of CMOS technology used in AR is presented. 3{sup left}H is a particularly important radioisotope used in AR because it can label many sites on biomolecules and provides the highest resolution images due to its low energy and hence low particle range compared to other beta-emitting radioisotopes. In order to detect β-particles from 3{sup left}H beta decay a back-thinned CMOS sensor has been used. Back-thinning is a standard process in CCDs but it is not widely applied to CMOS sensors. In this paper the first results of imaging a calibrated 3{sup left}H microscale and the first tritiated autoradiogram obtained with a back-thinned CMOS sensor at room temperature are presented.
While conventional approaches of BCI feature extraction are based on the power spectrum, we have tried using nonlinear features for classifying BCI data. In this paper, we report our test results and findings, which i...
While conventional approaches of BCI feature extraction are based on the power spectrum, we have tried using nonlinear features for classifying BCI data. In this paper, we report our test results and findings, which indicate that the proposed method is a potentially useful addition to current feature extraction techniques.
This paper is focused on multichannel radar array processing and addresses some challenging issues concerning: the adaptation in nonstationary and nonhomogeneous environments, the value of Space-Time Adaptive Processi...
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This paper is focused on multichannel radar array processing and addresses some challenging issues concerning: the adaptation in nonstationary and nonhomogeneous environments, the value of Space-Time Adaptive processing (STAP) in an operational High Frequency (HF) radar system, the benefits resulting from the joint use of multiple (not colocated) transmitters and receivers, and the parallel implementation of the multichannel processor. The work follows on where the importance of a multichannel processing is demonstrated with reference to airborne, ground-based, and Over The Horizon (OTH) radar systems.
In tile process of the reconstruction of digital holography. the traditional methods of diffraction and filtration are commonly adopted to recover the original complex-wave signal. Influenced by twin-image and zero-or...
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In tile process of the reconstruction of digital holography. the traditional methods of diffraction and filtration are commonly adopted to recover the original complex-wave signal. Influenced by twin-image and zero-order terms, the above-mentioned methods, however, either limit tile field of vision or result in the loss of the amplitude and phase. A new method for complex-wave retrieval is presented, which is based on blindsignal separation. Three frames of holograms are captured by a charge coupled device (CCD) camera to form an observation signal. The term containing only amplitude and phase of complex-wave is separated, by means of independent component analysis, from the observation signal, which effectively eliminates the zero-order term. Finally. the complex-wave retrieval of pure phase wavefront is achieved. Experimental results show that this method can better recover the amplitude and phase of the original complex-wave even when there is a frequency spectrum mixture in the hologram.
There is a growing interest in the frequency modulated continuous wave (FM-CW) SAR for its small cubage, light weight, cost-effective and high resolution. In this paper, the author deduced the imaging process in detai...
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ISBN:
(纸本)9780780395824
There is a growing interest in the frequency modulated continuous wave (FM-CW) SAR for its small cubage, light weight, cost-effective and high resolution. In this paper, the author deduced the imaging process in detail, discussed the production and the removing of Residual video phase (RVP) as well as the Slope factor, then the improved imaging algorithm is presented by combination de-sloping, range migration correction with pulse compression. The derivation and the simulation proved the algorithm is feasible and correct.
Most previous literature in the maneuvering target tracking community focus on 2D models or 3D models where target maneuvers mostly in a horizontal plane, and usually an acceptable accuracy can be expected when these ...
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