The advances in broadband Internet access and scalable video technologies have made it possible for Internet Protocol television (IPTV) to become the next killer application for modern Internet carriers in metropolita...
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The advances in broadband Internet access and scalable video technologies have made it possible for Internet Protocol television (IPTV) to become the next killer application for modern Internet carriers in metropolitan areas. With the recent release of IEEE 802.16d/e (worldwide interoperability for microwave access or WiMAX), broadband wireless access (BWA) is envisioned to further extend IPTV services to a new application scenario with wireless and mobility dimensions. It is a very strategic but challenging leverage for a carrier to glimpse the potential of IPTV by using WiMAX as the access network. Challenges are posed for IPTV over WiMAX due to multicasting under a diversity of fading conditions. A cross-layer design framework based on a novel two-level superposition coded multicasting (SCM) scheme is introduced. Simulation results show that much improved video quality is achievable with our approach.
Adding/subtracting one into/from pixel values can be used to hide secret data into the least significant bit plane of a cover image. A double-layered embedding scheme that introduces the wet paper coding mechanism to ...
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Adding/subtracting one into/from pixel values can be used to hide secret data into the least significant bit plane of a cover image. A double-layered embedding scheme that introduces the wet paper coding mechanism to determine the selection of addition or subtraction is proposed. In this way, the second LSB plane can be exploited to carry additional secret data, leading to improved embedding efficiency and embedding rate. By combining the double-layered embedding method with various steganographic coding techniques, even higher embedding efficiencies can be achieved while keeping low embedding rates.
Sparse coding is an important approach for the unsupervised learning of sensory features. In this contribution, we present two new methods that extend the traditional sparse coding approach with supervised components....
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Sparse coding is an important approach for the unsupervised learning of sensory features. In this contribution, we present two new methods that extend the traditional sparse coding approach with supervised components. Our goal is to increase the suitability of the learned features for classification tasks while keeping most of their general representation capability. We analyze the effect of the new methods using visualization on artificial data and discuss the results on two object test sets with regard to the properties of the found feature representation.
Minimal and maximal arrangements of hyperplanes in P-n (F-q). In this Note we study the arrangements of hyperplanes in a projective space such that the number of rational points of the union of these hyperplanes is mi...
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Minimal and maximal arrangements of hyperplanes in P-n (F-q). In this Note we study the arrangements of hyperplanes in a projective space such that the number of rational points of the union of these hyperplanes is minimal. These results apply to coding theory.
A 'queued-code' is a novel code which allows for instantaneous rate adaptation, to match the current channel state information (CSI), assumed known to the transmitter. Previously, information theoretic codes w...
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ISBN:
(纸本)9781424410422
A 'queued-code' is a novel code which allows for instantaneous rate adaptation, to match the current channel state information (CSI), assumed known to the transmitter. Previously, information theoretic codes were analyzed in the regime of large delay bounds. Numerical results had demonstrated the performance gain of these codes over fixed rate codes, in a range of situations. This paper presents queued-codes which are designed using low density parity check (LDPC) block codes. Simulation results demonstrate performance gain of these codes over fixed rate LDPC block codes. The simulation results are consistent with the numerical results obtained for the information theoretic codes, which is a satisfying result. Further, this paper argues for the use of rate adaptation within a codeword, as opposed to rate adaptation across codewords, when CSI is available at the transmitter.
Let F-n be the binary n-cube, or binary Hamming space of dimension n, endowed with the Hamming distance, and epsilon(n) (respectively, O-n) the set of vectors with even (respectively, odd) weight. For r >= 1 and x ...
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ISBN:
(纸本)9783540772231
Let F-n be the binary n-cube, or binary Hamming space of dimension n, endowed with the Hamming distance, and epsilon(n) (respectively, O-n) the set of vectors with even (respectively, odd) weight. For r >= 1 and x is an element of F-n, we denote by B-r (x) the ball of radius r and centre x. A code C subset of F-n n is said to be r-identifying if the sets B-r(x) boolean AND C, x is an element of F-n, are all nonempty and distinct. A code C subset of epsilon(n) is said to be r-discriminating if the sets B, (x) boolean AND C, x is an element of O-n, are all nonempty and distinct. We show that the two definitions, which were given for general graphs, are equivalent in the case of the Hamming space, in the following sense: for any odd r, there is a bijection between the set of r-identifying codes in F-n and the set of r-discriminating codes in Fn+l.
We study the relationship between the degree of blocking and the amount of resource speedup necessary for blocking switches to possess the capabilities of nonblocking switches. We construct an analogy between switch c...
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We study the relationship between the degree of blocking and the amount of resource speedup necessary for blocking switches to possess the capabilities of nonblocking switches. We construct an analogy between switch configurations and the codewords of certain error control codes for which we use space covering ideas to derive relations between speedup and number of switch configurations. To derive the necessary speedup for nonblocking, we use two sphere packing bounds: the Hamming bound and the Gilbert-Varshamov bound. To construct nonblocking switches with a given speedup we use maximum distance separable codes. We consider both multicast and point to point scenarios.
Our perceptive of the scientific datasets has largely relied on numerical and statistical analysis of data from experimental dimension and computer simulation result [4][14][11][12][13]. In particular, we consider a s...
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ISBN:
(纸本)9783540680161
Our perceptive of the scientific datasets has largely relied on numerical and statistical analysis of data from experimental dimension and computer simulation result [4][14][11][12][13]. In particular, we consider a simulated 3D time-varying model of scientific datasets and examine the temporal correlation among datasets. Our goal is to contrive effective visual representations to assist scientists in ascertaining temporal correlation among intricate and apparently chaotic scientific datasets. We propose a hybrid application with combination of streamline, global and local color scale and opacity scheme for spatio-temporal collaborative depiction. We illustrated also few images that can offer an effective tool for visually mining 3D time-varying scientific datasets.
Galois ring m-sequences were introduced in the late 1980s and early 1990s, and have near-optimal full periodic correlations. They are related to Z(4)-linear codes, and are used in COMA communications. We consider peri...
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ISBN:
(纸本)9781424410736
Galois ring m-sequences were introduced in the late 1980s and early 1990s, and have near-optimal full periodic correlations. They are related to Z(4)-linear codes, and are used in COMA communications. We consider periodic correlation and obtain algebraic expressions of the first two partial period correlation moments of these sequences. These correlation moments have applications in synchronisation performance of COMA systems using Galois ring m-sequences.
The Fourier spectrum characters of the almost perfect binary array pair are studied, which is based on the concept of the almost perfect binary array pair. The distributions of the weights, existent range and the unba...
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ISBN:
(纸本)1424411351
The Fourier spectrum characters of the almost perfect binary array pair are studied, which is based on the concept of the almost perfect binary array pair. The distributions of the weights, existent range and the unbalance of almost perfect binary array pair are given by using this spectrum characters.
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