This article presents a survey of state-of-the-art hardware designs optimizing the tradeoffs between security, power, and costs in ultra-low-power systems like the Internet of Things. The authors analyze the connectio...
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This article presents a survey of state-of-the-art hardware designs optimizing the tradeoffs between security, power, and costs in ultra-low-power systems like the Internet of Things. The authors analyze the connections between hardware specs and system demands to bridge the gap between research conducted in different communities. They also identify open problems in designing future ultra-low-power and secure hardware.
This article provided a survey of waveform adaptation algorithms for multiuser wireless communications based on noncooperative game theory. Emphasis has been given to the problem of spreading code optimization in CDMA...
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This article provided a survey of waveform adaptation algorithms for multiuser wireless communications based on noncooperative game theory. Emphasis has been given to the problem of spreading code optimization in CDMA systems, a research topic that has attracted the interest of many researchers for years, and some space has also been devoted to other applications of waveform adaptation algorithms, such as beamforming in multiantenna multiuser communications and waveform selection in cognitive radio networks. For these three research tracks we have reviewed the principal results pertaining to the issue of noncooperative waveform adaptation, and some open research problems have been discussed. We believe that, given the rapid pace at which wireless communications have been developing, waveform adaptation will play a key role in the future to enhance the performance of increasingly highly loaded wireless data networks.
The coordinate rotation digital computer (CORDIC) is a rotation-based arithmetic computing algorithm which has found many important digital signal processing applications. In this paper, a detailed analysis of the qua...
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The coordinate rotation digital computer (CORDIC) is a rotation-based arithmetic computing algorithm which has found many important digital signal processing applications. In this paper, a detailed analysis of the quantization error encountered in the CORDIC algorithm is presented. Two types of quantization error are examined: One is an approximation error due to the quantized representation of rotation angles. The other is a rounding error due to the finite precision representation in both fixed point and floating point arithmetic. Tight error bounds for these two types of error are derived. The rounding error due to a scaling (normalization) operation in the CORDIC algorithm is also discussed. Lastly, an expression for overall quantization error is derived and several simulation examples are presented.
Divide-and-conquer is a natural way to cope with the complexity of automatic testbench generation. The key to developing an effective divide-and-conquer approach is to identify the partitioning boundaries where intera...
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Divide-and-conquer is a natural way to cope with the complexity of automatic testbench generation. The key to developing an effective divide-and-conquer approach is to identify the partitioning boundaries where interactions among divided components are minimized. The authors propose a novel design decomposition scheme and show how it can help improve the performance of constraint solving for test generation.
The authors present a survey and a comparative analysis of various algorithms introduced for the differential protection of three-phase transformers. After a brief review of the concept, the problems associated with t...
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The authors present a survey and a comparative analysis of various algorithms introduced for the differential protection of three-phase transformers. After a brief review of the concept, the problems associated with the differential protection of transformers, and the existing solutions as implemented with conventional (electromagnetic) relays, the algorithms introduced for digital relaying are outlined. Some of these algorithms are derived from conventional protection methods while others represent novel methods. They are analyzed in view of how well they address the two subproblems of differential protection per se and exciting-current detection. Finally, a simple ranking procedure is introduced. Two optimality performance indices, based on time and frequency, are defined and used as a basis for a comparison of the algorithm presented.< >
A new parallel normalized optimized approximate inverse algorithm, based on the concept of the "fish bone" computational approach satisfying an antidiagonal data dependency, for computing classes of explicit...
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A new parallel normalized optimized approximate inverse algorithm, based on the concept of the "fish bone" computational approach satisfying an antidiagonal data dependency, for computing classes of explicit approximate inverses, is introduced for symmetric multiprocessor systems. The parallel normalized explicit approximate inverses are used in conjunction with parallel normalized explicit preconditioned conjugate gradient square schemes, for the efficient solution of finite element sparse linear systems. The parallel design and implementation issues of the new proposed algorithms are discussed and the parallel performance is presented, using OpenMP. (c) 2007 Elsevier Inc. All rights reserved.
A tracking analysis of the adaptive filters equipped with the sign algorithm and operating in nonstationary environments is presented. Under the assumption that the nonstationary can be modeled using a random disturba...
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A tracking analysis of the adaptive filters equipped with the sign algorithm and operating in nonstationary environments is presented. Under the assumption that the nonstationary can be modeled using a random disturbance, it is shown that the long-term time average of the mean-absolute error is bounded, and that there exists an optimal choice of the convergence constant mu which minimizes this quality. Applying the commonly used independence assumption, and under the assumption that the nonstationarity is solely due to the time-varying behavior of the optimal coefficients, it is shown that the distributions of the successive coefficient misalignment vectors converge to a limiting distribution when the adaptive filter is used in the system identification mode. Finally, under the additional assumption that the signals involved are zero mean and Gaussian, a set of nonlinear difference equations is derived that characterizes the mean and mean-squared behavior of the filter coefficients and the mean-squared estimation error during adaptation and tracking. Results of several experiments that show very good correlation with the theoretical analyses are presented.< >
This article introduces the basic Quicksort algorithm and gives a flavor of the richness of its complexity analysis. The author also provides a glimpse of some of its generalizations to parallel algorithms and computa...
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This article introduces the basic Quicksort algorithm and gives a flavor of the richness of its complexity analysis. The author also provides a glimpse of some of its generalizations to parallel algorithms and computational geometry.
An efficient algorithm is presented for the computation of grayscale morphological operations with arbitrary 2-D flat structuring elements (S.E.). The required computing time is independent of the image content and of...
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An efficient algorithm is presented for the computation of grayscale morphological operations with arbitrary 2-D flat structuring elements (S.E.). The required computing time is independent of the image content and of the number of gray levels used. It always outperforms the only existing comparable method, which was proposed in the work by Van Droogenbroeck and Talbot, by a factor between 3.5 and 35.1, depending on the image type and shape of S.E. So far, filtering using multiple S.E.s is always done by performing the operator for each size and shape of the S.E. separately. With our method, filtering with multiple S.E.s can be performed by a single operator for a slightly reduced computational cost per size or shape, which makes this method more suitable for use in granulometries, dilation-erosion scale spaces, and template matching using the hit-or-miss transform. The discussion focuses on erosions and dilations, from which other transformations can be derived.
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