THz wave generated by difference-frequency in nonlinear crystal in normal temperature is theoretically studied. The conclifton of phase matching is deduced and an experimental setup is proposed. With this method, THz ...
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THz wave generated by difference-frequency in nonlinear crystal in normal temperature is theoretically studied. The conclifton of phase matching is deduced and an experimental setup is proposed. With this method, THz wave can be generated without rigorous condition and can work continuously for a long period of time in room temperature.
This paper presents a novel algorithm for point correspondences using graph spectral analysis. Firstly, the correspondence probabilities are computed by using the eigenvectors and eigenvalues of the proximity matrix a...
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This paper presents a novel algorithm for point correspondences using graph spectral analysis. Firstly, the correspondence probabilities are computed by using the eigenvectors and eigenvalues of the proximity matrix as well as the method of alternated row and column normalizations. Secondly, local similarity evaluated by shape context is incorporated into our spectral method to refine the results of spectral correspondence via a probabilistic relaxation approach. Experiments on both real-world and synthetic data show that our method possesses comparatively high accuracy.
In this paper, a parallel genetic algorithm for finding all roots of complex functional equation based on Parallel Virtual Machine (PVM) is present, research are made in some technical problems for realizing. We descr...
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In this paper, a parallel genetic algorithm for finding all roots of complex functional equation based on Parallel Virtual Machine (PVM) is present, research are made in some technical problems for realizing. We describe the design and implement of parallel genetic algorithm for finding roots complex functional equation.
A novel image content authentication algorithm based on Laplace spectra was proposed. Outstanding feature points are extracted from the original image and a cipher point is inserted. A relational graph is then built, ...
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A novel image content authentication algorithm based on Laplace spectra was proposed. Outstanding feature points are extracted from the original image and a cipher point is inserted. A relational graph is then built, and the Laplace spectra of the graph are calculated to serve as image features. The Laplace spectra are quantized then embedded into the original image as a watermark. In the authentication step, the Laplace spectra of the authenticating image are calculated and compared with that of the watermark embedded in the authenticating image. If both of the spectra are identical, the image passes the authentication test. Otherwise, the tamper is found. The experimental results show that the proposed authentication algorithm can effectively detect the event and the location when the original image content is tampered viciously.
Learning methods of constructive neural network aims to overcome the disadvantages of BP algorithm, which has many advantages such as fast convergent rate, less computation, good fault-tolerant and strong generalizati...
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ISBN:
(纸本)9781615677214
Learning methods of constructive neural network aims to overcome the disadvantages of BP algorithm, which has many advantages such as fast convergent rate, less computation, good fault-tolerant and strong generalization ability, etc. Its structure is constructed step by step in the processing of the data rather than being prescribed in advance. This paper mainly introduces the developing motivations, research status quo and development directions, laying stress on two kinds of constructive learning methods: FP algorithm and covering algorithm. After discussing the construction and basic properties of FP network, we construct an FP network as a general clustering unit, and analyze its main properties. On the base of summarizing covering algorithm we present a general neighborhood covering algorithm and its corresponding network. According to the characteristics of the algorithm we analyze its existing problems and propose the further research orientations.
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.
In this paper, we use the relations of quotient space theory and martingale therory to research the iterated function system that is fractal geometry images, and propose these conclusions: Given an irreducible iterate...
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ISBN:
(纸本)7900719229
In this paper, we use the relations of quotient space theory and martingale therory to research the iterated function system that is fractal geometry images, and propose these conclusions: Given an irreducible iterated function system {X,wipij;i,j = 1,2,}, then exists a corresponding chain of quotient space {Wk = (Xk, μk,Fk);&=1,2,:} and a martingale {(μk, Fk );k = 1,2,}on the chain, therefore there are: l)Assume Pk is a invariant subsets of Wk, P is a invariant subsets of W, then exists lim k&rarr∞ Pk =P and the convergence is according to Hausdorff distance. 2)Assume μk is a invariant measure of Fk, μ is a invariant measure of F, then exists limμk k&rarr∞=μ 3) Pk is a support set of μk, P is a support set of μ Namely we present the quotient approximation theorem about fractal geometry images, and build relations among chain of quotient space, martingale, fractal geometry images and Markovian process.
In this paper, we summarize the characteristics of message search mechanism of Gnutella P2P network model. By analyzing its disadvantages, an improvement of resource discovery algorithm is proposed, it can more effect...
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In this paper, we summarize the characteristics of message search mechanism of Gnutella P2P network model. By analyzing its disadvantages, an improvement of resource discovery algorithm is proposed, it can more effectively reduce network traffic than the existing search methods in Gnutella system, and it can also improve Gnutella network's integrity, availability and scalability.
This paper proposes an indexing scheme based on t- mixture model and ICA, which is more robust than Gaussian mixture modeling when atypical points (or outliers) exist or the set of data has heavy tail. This indexing s...
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This paper proposes an indexing scheme based on t- mixture model and ICA, which is more robust than Gaussian mixture modeling when atypical points (or outliers) exist or the set of data has heavy tail. This indexing scheme combines optimized vector quantizer and probabilistic approximate-based indexing scheme. Experimental results on large-scale graph database show a notable efficiency improvement with optimistic precision.
Video abstraction plays an important role in video browsing, video indexing, video retrieval and other video applications. In the paper, an automatic video abstraction method is developed based on relational graph rep...
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Video abstraction plays an important role in video browsing, video indexing, video retrieval and other video applications. In the paper, an automatic video abstraction method is developed based on relational graph representations. Firstly, a relational graph is constructed for all the frames in a video sequence. Secondly, the graph is partitioned into different connected subgraphs. Thirdly, Isomap is performed to reduce the dimensionality of the data set, and the output of Isomap is used as feature vector of the video frames. Lastly, a mixture model with model selection is introduced to generate the fine grain video abstraction with the centre of each clustering as the keyframes. Experiments are conducted on real world video sets with satisfying video abstraction results.
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