Passage of the Digital Millennium Copyright Act (DMCA) was a significant milestone in congressional information policy legislation. However, the results were widely criticized in some circles as providing too much pow...
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Passage of the Digital Millennium Copyright Act (DMCA) was a significant milestone in congressional information policy legislation. However, the results were widely criticized in some circles as providing too much power to certain stakeholder groups. This paper uses computer-based content analysis and a theoretical taxonomy of information policy values to analyze congressional hearing testimony. The results of document coding were then analyzed using a variety of statistical tools to map how different stakeholders framed issues in the debate and determine if congressional value statements about the legislation conformed more closely to certain stakeholders. Results of the analysis indicate that significant differences in the use of information policy terms occurred across stakeholders, and showed varying degrees of convergence between congressional or other stakeholders when framing information policy issues.
This paper presents the performance of the Weight-Balanced Testing (WBT) algorithm with multiple testers. The WBT algorithm aims to minimize the expected number of ( round of) tests and has been proposed for coding, m...
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This paper presents the performance of the Weight-Balanced Testing (WBT) algorithm with multiple testers. The WBT algorithm aims to minimize the expected number of ( round of) tests and has been proposed for coding, memory storage, search and testing applications. It often provides reasonable results if used with a single tester. Yet, the performance of the WBT algorithm with multiple testers and particularly its upper bound have not been previously analyzed, despite the large body of literature that exists on the WBT algorithm, and the recent papers that suggest its use in various testing applications. Here we demonstrate that WBT algorithm with multiple testers is far from being the optimal search procedure. The main result of this paper is the generalization of the upper bound on the expected number of tests previously obtained for a single-tester WBT algorithm. For this purpose, we first draw an analogy between the WBT algorithm and alphabetic codes;both being represented by the same Q-ary search tree. The upper bound is then obtained on the expected path length of a Q-ary tree, which is constructed by the WBT algorithm. Applications to the field of testing and some numerical examples are presented for illustrative purposes.
Selecting an efficient variable block size mode in H.264 video coding standard for better compression performance is considered. The proposed scheme is based on a 3D recursive search algorithm and takes into account t...
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Selecting an efficient variable block size mode in H.264 video coding standard for better compression performance is considered. The proposed scheme is based on a 3D recursive search algorithm and takes into account the motion vector cost and previous frame information. The best mode for the current macroblock is obtained by analysing the modes for a maximum of four macroblocks in the current and previous frames. An improvement in the encoding time with negligible impact on subjective and quantitative performance has been achieved.
The use of coding for error control is an integral part of the design of modern communication systems. Capacity-approaching codes such as turbo and LDPC codes, discovered or rediscovered in the past decade, offer near...
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The use of coding for error control is an integral part of the design of modern communication systems. Capacity-approaching codes such as turbo and LDPC codes, discovered or rediscovered in the past decade, offer near-Shannon-limit performance on the AWGN channel with rather low implementation complexity and are therefore increasingly being applied for error control in various fields of data communications. This article describes a generic multilevel modulation and coding scheme based on the use of turbo, turbo-like, or LDPC codes for DSL systems. It is shown that such codes provide significant gains in performance and allow an increase in data rate and/or loop reach that can be instrumental to the widespread deployment of future DSL services. Such techniques are also suitable for general multilevel modulation systems in other application areas.
Cryptography and coding theory are closely related in many respects. Recently, the problem of "decoding Reed Solomon codes" (also known as "polynomial reconstruction") was suggested as an intractab...
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Cryptography and coding theory are closely related in many respects. Recently, the problem of "decoding Reed Solomon codes" (also known as "polynomial reconstruction") was suggested as an intractability assumption to base the security of protocols on. This has initiated a line of cryptographic research exploiting the rich algebraic structure of the problem and its variants. In this paper we give a short overview of the recent works in this area as well as list directions and open problems in Polynomial Reconstruction Based Cryptography.
Digital signal processing and coding are increasingly being recognized as a cost-efficient approach in achieving substantial areal density gains while preserving the high reliability of disk drives, although historica...
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Digital signal processing and coding are increasingly being recognized as a cost-efficient approach in achieving substantial areal density gains while preserving the high reliability of disk drives, although historically advances in head and media technologies have been the main driving force behind areal density growth. The recent advances in capacity-approaching codes hold the promise to push the areal density to the ultimate limit. In this article the various configurations regarding the interplay between soft detection and soft decoding through an iterative process, as it applies to the magnetic recording channel, are presented. In particular, the state of the art in turbo and turbo-like coding, including LDPC coding, is reviewed, and the serial concatenation of these coding schemes with inner generalized PR channels in a turbo equalization structure is described. Finally, an attempt is made to assess the performance and limitations of these AWGN channel-capacity-approaching codes when applied to the magnetic recording channel.
Dr. Atal was chosen for his fundamental contributions to speech coding in digital cellular telephony-specifically for pioneering work in linear predictive coding (LPC) and use of analysis-by-synthesis leading to multi...
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Dr. Atal was chosen for his fundamental contributions to speech coding in digital cellular telephony-specifically for pioneering work in linear predictive coding (LPC) and use of analysis-by-synthesis leading to multi-pulse excited linear predictive coding and code excited linear predictive coding (CELP). These are the basis of time-division and code-division cellular systems (TDMA & CDMA), the Nextel system, and the global system for mobile communications (GSM). (C) 2004 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.
The multicovering radius is a generalization of the covering radius. In this correspondence, we show that lower-bounding the m-covering radius of an arbitrary binary code is NP-complete when m is polynomial in the len...
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The multicovering radius is a generalization of the covering radius. In this correspondence, we show that lower-bounding the m-covering radius of an arbitrary binary code is NP-complete when m is polynomial in the length of the code. Lower-bounding the m-covering radius of a linear code is Sigma(2)(p)-complete when m is polynomial in the length of the code. If P is not equal to NP, then the m-covering radius of an arbitrary binary code cannot be approximated within a constant factor or within a factor n(epsilon) where n is the length of the code and epsilon < 1, in polynomial time. Note that the case when m = 1 was also previously unknown. If NP is not equal to Sigma(2)(p), then the m-covering radius of a linear code cannot be approximated Within a constant factor or within a factor n(epsilon) where n is the length of the code and epsilon < 1, in polynomial time.
The problem of selecting codewords for memoryless low-power bus coding is considered. A graph-based procedure is proposed to obtain a subset of all possible codewords with minimum average energy consumption. The proce...
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The problem of selecting codewords for memoryless low-power bus coding is considered. A graph-based procedure is proposed to obtain a subset of all possible codewords with minimum average energy consumption. The procedure can be applied to arbitrary cost models.
We look at Berlekamp's switching game of n x n grids for n greater than or equal to 10. We show that the previous result for R 10 was incorrect, and that in fact R-10 = 35. We also show that R-11 = 43 and R-12 = 5...
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We look at Berlekamp's switching game of n x n grids for n greater than or equal to 10. We show that the previous result for R 10 was incorrect, and that in fact R-10 = 35. We also show that R-11 = 43 and R-12 = 54, and give new lower bounds for R-13 through R-20. 0 2004 Elsevier B.V. All rights reserved.
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