The design of a good kernel is fundamental for knowledge discovery from graph-structured data. Existing graph kernels exploit only limited information about the graph structures but are still computationally expensive...
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ISBN:
(纸本)9781424452422
The design of a good kernel is fundamental for knowledge discovery from graph-structured data. Existing graph kernels exploit only limited information about the graph structures but are still computationally expensive. We propose a novel graph kernel based on the structural characteristics of graphs. The key is to represent node labels as binary arrays and characterize each node using logical operations on the label set of the connected nodes. Our kernel has a linear time complexity with respect to the number of nodes times the average number of neighboring nodes in the given graphs. The experimental result shows that the proposed kernel performs comparable and much faster than a state-of-the-art graph kernel for benchmark data sets and shows high scalability for new applications with large graphs.
The McEliece-Sidel'nikov cryptosystem is a modification of the McEliece cryptosystem, which is one of the oldest public-key cryptosystems. It was proposed by V. M. Sidel'nikov in 1994 and is based on the u-fol...
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In order to realize error free communication we have to add appropriate redundancy to the transmitted bit stream. This can be achieved using the Convolutional code. There are a number of techniques for decoding Convol...
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ISBN:
(纸本)9781424445189
In order to realize error free communication we have to add appropriate redundancy to the transmitted bit stream. This can be achieved using the Convolutional code. There are a number of techniques for decoding Convolutional code. The method used in this work is the Viterbi algorithm which performs maximum likelihood decoding. This work will give an overview to the convolution encoder and the Viterbi decoder. Furthermore, the simulation environment using MATLAB tool in the evaluation of the performance of the decoder with additive white Gaussian noise channel will be considered.
The popular logic puzzle, Sudoku, consists of placing the digits 1,...,9 into a 9 x 9 grid, such that each digit appears only once in each row, column, and subdivided 'mini-grid' of size 3 x 3. Uniqueness of s...
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ISBN:
(纸本)9789898111661
The popular logic puzzle, Sudoku, consists of placing the digits 1,...,9 into a 9 x 9 grid, such that each digit appears only once in each row, column, and subdivided 'mini-grid' of size 3 x 3. Uniqueness of solution of a puzzle is ensured by the positioning of a number of given values. Quasi-Magic Sudoku adds the further constraint that within each mini-grid, every row, column and diagonal must sum to 15 +/-Delta, where Delta is chosen to take a value between 2 and 8. Recently Sudoku has been shown to have potential for the generation of erasure correction codes. The additional quasi-magic constraint results in far fewer given values being required to ensure uniqueness of solution, raising the prospect of improved usefulness in code generation. Recent work has highlighted useful domain knowledge concerning cell interrelationships in Quasi-Magic Sudoku for the case Delta = 2, providing pruning conditions to reduce the size of search space that need be examined to ensure uniqueness of solution. This paper examines the usefulness of the identified rich knowledge in restricting search space size. The knowledge is implemented as pruning conditions in a backtracking implementation of a Quasi-Magic Sudoku solver, with a further cell ordering heuristic. Analysis of the improvement in processing time, and thereby of the potential usefulness of Quasi-Magic Sudoku for code generation, is provided.
Determining the minimum distance of a linear code is one of the most important problems in algorithmic coding theory. The exact version of the problem was shown to the NP-complete in [14]. In [8], the gap version of t...
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ISBN:
(纸本)9781605586137
Determining the minimum distance of a linear code is one of the most important problems in algorithmic coding theory. The exact version of the problem was shown to the NP-complete in [14]. In [8], the gap version of the problem was shown to be NP-hard for any constant factor under a randomized reduction. It was shown in the same paper that the minimum distance problem is not approximable in randomized polynomial time to the factor 2(log1-epsilon n) unless NP subset of RTIME(2(polylog(n))). In this paper, we derandomize the reduction and thus prove that there is no deterministic polynomial time algorithm to approximate the minimum distance to any constant factor unless P = NP. We also prove that the minimum distance is not approximable in deterministic polynomial tome to the factor 2(log1-epsilon) n unless NP subset of DTIME (2(polylog(n))). As the main technical contribution, for any constant 2/3 < rho < 1, we present a deterministic algorithm that give a positive integer s, runs in time poly(s) and constructs a code C of length poly(s) with an explicit Hamming ball of radius rho d(C) such that a projection at some s coordinates sends the codewords in the ball subjectively onto a linear subspace of dimension s, where d(C) denotes the minimum distance of C. The codes are obtained by concatenating Reed-Solomon codes with Hadamard codes.
The classical Simon effect shows that actions are carried out faster if they spatially correspond to the stimulus signaling them. Recent studies revealed that this is the case even when the two actions are carried out...
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The classical Simon effect shows that actions are carried out faster if they spatially correspond to the stimulus signaling them. Recent studies revealed that this is the case even when the two actions are carried out by different people;this finding has been taken to imply that task representations are socially shared. In work described here, we found that the "interactive" Simon effect occurs only if actor and coactor are involved in a positive relationship (induced by a friendly-acting, cooperative confederate), but not if they are involved in a negative relationship (induced by an intimidating, competitive confederate). This result suggests that agents can represent self-generated and other-generated actions separately, but tend to relate or integrate these representations if the personal relationship between self and other has a positive valence.
In several wireless applications multiple sources transmit information to one or more receivers, many times over unknown topologies. This is especially so in mobile networks where learning the topology may have prohib...
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ISBN:
(纸本)9781605585215
In several wireless applications multiple sources transmit information to one or more receivers, many times over unknown topologies. This is especially so in mobile networks where learning the topology may have prohibitive complexity. Network coding techniques allow to achieve the min-cut capacity even when the topology is unknown. Our contribution in this paper is to develop algebraic code constructions for multiple sources network coding.
Video communication has received tremendous attention from both academia and industry. The conventional hybrid video coding scheme has demonstrated state-of-the-art coding performance. However, its application in vide...
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Video communication has received tremendous attention from both academia and industry. The conventional hybrid video coding scheme has demonstrated state-of-the-art coding performance. However, its application in video communication still faces several challenges, such as the transmission error of the wireless networks and the power limitation of the hand-held devices. The purpose of this research is to investigate novel algorithms to address the aforementioned issues in conventional hybrid video coding schemes. This work consists of two major parts as follows. The first part investigates the novel applications and further advances of the newly emerged Wyner-Ziv video coding (WZVC) algorithm. Central to the WZVC is the correlation estimation problem. The accuracy of this correlation estimation has big impact on the coding efficiency of WZVC. In this thesis we investigate this problem and propose a universal solution to a general WZVC scheme. Based on progressive learning and convex optimization, the proposed method achieves considerable gain over the existing methods; One promising application of WZVC is low complexity encoding. In this thesis we investigate using Wyner-Ziv successive refinement (WZSR) in such application to improve the coding efficiency. We also conduct rate-distortion analysis and prove that the loss due to decoder motion estimation is limited to less than 2.17dB using the proposed WZSR based scheme. This result, comparing with the existing analysis result, yields that the proposed scheme can gain 4dB in some cases over the original WZVC scheme; WZVC is flexible in that the decoder can reconstruct the video almost identically even if using different prediction frames. Based on this feature, we propose a novel Wyner-Ziv based bidirectionally decodable (WZ-BID) video coding scheme and the corresponding video streaming system. This system achieves three major functionalities: reverse playback, stream switching and error resilience simultaneously. We
A scheme of the generation of entangled qutrits is presented, and then is generalized to entangled ququads and entangled qudits. With the entangled qutrits, an experimental scheme of probability superdense coding with...
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A scheme of the generation of entangled qutrits is presented, and then is generalized to entangled ququads and entangled qudits. With the entangled qutrits, an experimental scheme of probability superdense coding with only linear optical elements is proposed. It is shown that this scheme will be suitable for the entangled ququads, even for the entangled qudits if some nonlinearity is used. This scheme is feasible in the laboratory with the current experimental technology.
In 1998, J. P. Hansen introduced the construction of an error-correcting code over afinite field Fq from a convex integral polytope in R2. Given a polytope P ⊂ R2, thereis an associated toric variety XP , and Hansen u...
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In 1998, J. P. Hansen introduced the construction of an error-correcting code over a
finite field Fq from a convex integral polytope in R2. Given a polytope P ⊂ R2, there
is an associated toric variety XP , and Hansen used the cohomology and intersection
theory of divisors on XP to determine explicit formulas for the dimension and minimum
distance of the associated toric code CP . We begin by reviewing the basics
of algebraic coding theory and toric varieties and discuss how these areas intertwine
with discrete geometry. Our first results characterize certain polygons that generate
and do not generate maximum distance separable (MDS) codes and Almost-MDS
codes. In 2006, Little and Schenck gave formulas for the minimum distance of certain
toric codes corresponding to smooth toric surfaces with rank(Pic(X)) = 2 and
rank(Pic(X)) = 3. Additionally, they gave upper and lower bounds on the minimum
distance of an arbitrary toric code CP by finding a subpolygon of P with a maximal,
nontrivial Minkowski sum decomposition. Following this example, we give explicit
formulas for the minimum distance of toric codes associated with two families of
smooth toric threefolds with rank(Pic(X)) = 2, characterized by G. Ewald and A.
Schmeinck in 1993. Lastly, we give explicit formulas for the dimension of a toric code
generated from a Minkowski sum of a finite number of polytopes in R2 and R3 and a
lower bound for the minimum distance.
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