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Awad G.,Dakota Consulting Inc | Over P.,U.S. National Institute of Standards and Technology | Kraaij W.,TNO | Kraaij W.,Radboud University Nijmegen
ACM Transactions on Information Systems | Year: 2014

This article presents an overview of the video copy detection benchmarkwhichwas run over a period of 4 years (2008-2011) as part of the TREC Video Retrieval (TRECVID) workshop series. The main contributions of the article include i) an examination of the evolving design of the evaluation framework and its components (system tasks, data, measures); ii) a high-level overview of results and best-performing approaches; and iii) a discussion of lessons learned over the four years. The content-based copy detection (CCD) benchmark worked with a large collection of synthetic queries, which is atypical for TRECVID, as was the use of a normalized detection cost framework. These particular evaluation design choices are motivated and appraised. Source


Sonmez M.T.,U.S. National Institute of Standards and Technology | Sonmez M.T.,Dakota Consulting Inc | Peralta R.,U.S. National Institute of Standards and Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

A generic way to design lightweight cryptographic primitives is to construct simple rounds using small nonlinear components such as 4×4 S-boxes and use these iteratively (e.g., PRESENT [1] and SPONGENT [2]). In order to efficiently implement the primitive, efficient implementations of its internal components are needed. Multiplicative complexity of a function is the minimum number of AND gates required to implement it by a circuit over the basis (AND, XOR, NOT). It is known that multiplicative complexity is exponential in the number of input bits n. Thus it came as a surprise that circuits for all 65 536 functions on four bits were found which used at most three AND gates [3]. In this paper, we verify this result and extend it to five-variable Boolean functions. We show that the multiplicative complexity of a Boolean function with five variables is at most four. © Springer International Publishing Switzerland 2015 (outside the US) Source


Goodwillie C.,East Carolina University | Ness J.M.,Dakota Consulting Inc
American Journal of Botany | Year: 2013

Premise of the study: The roles of hybridization and mating systems in the evolution of angiosperms have been well studied, but less work has focused on their interactions. Self-incompatible and self-compatible species often show asymmetry in hetero-specific pollen rejection. Self-fertilization can preempt ovules before opportunities for hybridization. In turn, hybridization might affect mating system evolution through selection for selfing to avoid production of low fitness hybrids. Methods: AFLP and morphological analyses were used to test for hybrids in a contact zone between species with contrasting breeding systems. Crossing experiments examined the relative contributions to reproductive isolation of pollen-pistil interactions, timing of self-fertilization, and F 1 viability and fertility. A diallel cross of siblings tested for an association between heterospecific incompatibility and S -genotype in the self-incompatible species. Key results: A low frequency of hybrids was detected in the contact zone. Pollen-pistil interactions were partially consistent with the SI × SC rule; some individuals of the self-incompatible species rejected heterospecific pollen, whereas the self-compatible species was fully receptive to it. In the selfing species, individuals with early selfing produced fewer hybrid progeny than did those with delayed self-compatibility when heterospecific pollen was applied after self-pollen. Viability of F 1s was high but fertility was low. Variability in heterospecific pollen rejection was not related to S-genotype. Conclusions: Both self-fertilization and self-incompatibility are associated with limits to hybridization at this site. The strong effect of timing of selfing on production of low fitness F 1 s suggests that hybridization might select for early selfing in this population. © 2013 Botanical Society of America. Source


Minnikanti S.,Dakota Consulting Inc | Minnikanti S.,U.S. National Institute of Standards and Technology | Gangopadhyay A.,George Mason University | Gangopadhyay A.,U.S. National Institute of Standards and Technology | Reyes D.R.,U.S. National Institute of Standards and Technology
Polymers | Year: 2014

The formation of polyelectrolyte multilayers (PEMs) for the first time, two decades ago, demonstrating the assembly on charged substrates in a very simple and efficient way, has proven to be a reliable method to obtain structures tunable at the nanometer scale. Much effort has been put into the assembly of these structures for their use in biological applications. A number of these efforts have been in combination with microfluidic systems, which add to the nanoassembly that is already possible with polyelectrolytes, a new dimension in the construction of valuable structures, some of them not possible with conventional systems. This review focuses on the advancements demonstrated by the combination of PEMs and microfluidic systems, and their use in biological applications. © 2014 by the authors. Source


Kelsey J.,U.S. National Institute of Standards and Technology | McKay K.A.,U.S. National Institute of Standards and Technology | Turan M.S.,U.S. National Institute of Standards and Technology | Turan M.S.,Dakota Consulting Inc
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

Random numbers are essential for cryptography. In most real-world systems, these values come from a cryptographic pseudorandom number generator (PRNG), which in turn is seeded by an entropy source. The security of the entire cryptographic system then relies on the accuracy of the claimed amount of entropy provided by the source. If the entropy source provides less unpredictability than is expected, the security of the cryptographic mechanisms is undermined, as in [5, 7, 10]. For this reason, correctly estimating the amount of entropy available from a source is critical. In this paper, we develop a set of tools for estimating entropy, based on mechanisms that attempt to predict the next sample in a sequence based on all previous samples. These mechanisms are called predictors. We develop a framework for using predictors to estimate entropy, and test them experimentally against both simulated and real noise sources. For comparison, we subject the entropy estimates defined in the August 2012 draft of NIST Special Publication 800-90B [4] to the same tests, and compare their performance. © International Association for Cryptologic Research 2015. Source

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