9,761 research outputs found
Self-checking on-line testable static RAM
This is a fault-tolerant random access memory for use in fault-tolerant computers. It comprises a plurality of memory chips each comprising a plurality of on-line testable and correctable memory cells disposed in rows and columns for holding individually addressable binary bits and provision for error detection incorporated into each memory cell for outputting an error signal whenever a transient error occurs therein. In one embodiment, each of the memory cells comprises a pair of static memory sub-cells for simultaneously receiving and holding a common binary data bit written to the memory cell and the error detection provision comprises comparator logic for continuously sensing and comparing the contents of the memory sub-cells to one another and for outputting the error signal whenever the contents do not match. In another embodiment, each of the memory cells comprises a static memory sub-cell and a dynamic memory sub-cell for simultaneously receiving and holding a common binary data bit written to the memory cell and the error detection provision comprises comparator logic for continuously sensing and comparing the contents of the static memory sub-cell to the dynamic memory sub-cell and for outputting the error signal whenever the contents do not match. Capability for correction of errors is also included
Phase Diagram Of The Biham-Middleton-Levine Traffic Model In Three Dimensions
We study numerically the behavior of the Biham-Middleton-Levine traffic model
in three dimensions. Our extensive numerical simulations show that the phase
diagram for this model in three dimensions is markedly different from that in
one and two dimensions. In addition to the full speed moving as well as the
completely jamming phases, whose respective average asymptotic car speeds
equal one and zero, we observe an extensive region of car densities with
a low but non-zero average asymptotic car speed. The transition from this
extensive low average asymptotic car speed region to the completely jamming
region is at least second order. We argue that this low speed region is a
result of the formation of a spatially-limited-extended percolating cluster.
Thus, this low speed phase is present in dimensional
Biham-Middleton-Levine model as well.Comment: Minor clarifications, 1 figure adde
Fourier Series Formalization in ACL2(r)
We formalize some basic properties of Fourier series in the logic of ACL2(r),
which is a variant of ACL2 that supports reasoning about the real and complex
numbers by way of non-standard analysis. More specifically, we extend a
framework for formally evaluating definite integrals of real-valued, continuous
functions using the Second Fundamental Theorem of Calculus. Our extended
framework is also applied to functions containing free arguments. Using this
framework, we are able to prove the orthogonality relationships between
trigonometric functions, which are the essential properties in Fourier series
analysis. The sum rule for definite integrals of indexed sums is also
formalized by applying the extended framework along with the First Fundamental
Theorem of Calculus and the sum rule for differentiation. The Fourier
coefficient formulas of periodic functions are then formalized from the
orthogonality relations and the sum rule for integration. Consequently, the
uniqueness of Fourier sums is a straightforward corollary.
We also present our formalization of the sum rule for definite integrals of
infinite series in ACL2(r). Part of this task is to prove the Dini Uniform
Convergence Theorem and the continuity of a limit function under certain
conditions. A key technique in our proofs of these theorems is to apply the
overspill principle from non-standard analysis.Comment: In Proceedings ACL2 2015, arXiv:1509.0552
Diversity and biosynthetic potential of culturable microbes associated with toxic marine animals
Tetrodotoxin (TTX) is a neurotoxin that has been reported from taxonomically diverse organisms across 14 different phyla. The biogenic origin of tetrodotoxin is still disputed, however, TTX biosynthesis by host-associated bacteria has been reported. An investigation into the culturable microbial populations from the TTX-associated blue-ringed octopus Hapalochlaena sp. and sea slug Pleurobranchaea maculata revealed a surprisingly high microbial diversity. Although TTX was not detected among the cultured isolates, PCR screening identifiedsome natural product biosynthesis genes putatively involved in its assembly. This study is the first to report on the microbial diversity of culturable communities from H. maculosa and P. maculata and common natural product biosynthesis genes from their microbiota. We also reassess the production of TTX reported from three bacterial strains isolated from the TTX-containing gastropod Nassarius semiplicatus
Relation Between Quantum Speed Limits And Metrics On U(n)
Recently, Chau [Quant. Inform. & Comp. 11, 721 (2011)] found a family of
metrics and pseudo-metrics on -dimensional unitary operators that can be
interpreted as the minimum resources (given by certain tight quantum speed
limit bounds) needed to transform one unitary operator to another. This result
is closely related to the weighted -norm on . Here we
generalize this finding by showing that every weighted -norm on
with 1\le p \le \limitingp induces a metric and a
pseudo-metric on -dimensional unitary operators with quantum
information-theoretic meanings related to certain tight quantum speed limit
bounds. Besides, we investigate how far the correspondence between the
existence of metrics and pseudo-metrics of this type and the quantum speed
limits can go.Comment: minor amendments, 6 pages, to appear in J.Phys.
Quantum Convolutional Error Correcting Codes
I report two general methods to construct quantum convolutional codes for
-state quantum systems. Using these general methods, I construct a quantum
convolutional code of rate 1/4, which can correct one quantum error for every
eight consecutive quantum registers.Comment: Minor revisions and clarifications. To appear in Phys. Rev.
Numerical study on the correlation between CP violation in neutrino oscillations and baryogenesis
We numerically study the correlation between CP violation in the neutrino
oscillations and baryogenesis in the seesaw model. In this study we get the
heavy Majorana neutrino masses and lepton number asymmetries from their decays
by fitting the data of neutrino oscillations and by working on some hypothesis
of the Dirac-Yukawa term for neutrinos.Comment: 3 pages, 2 figures, Latex, presented at KEKTC5(Nov. 2001), to be
published in Nucl. Phys. Proc. Supp
Beamforming in Two-Way Fixed Gain Amplify-and-Forward Relay Systems with CCI
We analyze the outage performance of a two-way fixed gain amplify-and-forward
(AF) relay system with beamforming, arbitrary antenna correlation, and
co-channel interference (CCI). Assuming CCI at the relay, we derive the exact
individual user outage probability in closed-form. Additionally, while
neglecting CCI, we also investigate the system outage probability of the
considered network, which is declared if any of the two users is in
transmission outage. Our results indicate that in this system, the position of
the relay plays an important role in determining the user as well as the system
outage probability via such parameters as signal-to-noise imbalance, antenna
configuration, spatial correlation, and CCI power. To render further insights
into the effect of antenna correlation and CCI on the diversity and array
gains, an asymptotic expression which tightly converges to exact results is
also derived.Comment: Accepted for presentation on IEEE International Conference on
Communications (ICC 2012), Ottawa, Canada, June 201
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