580 research outputs found
Strongly Universal Reversible Gate Sets
It is well-known that the Toffoli gate and the negation gate together yield a
universal gate set, in the sense that every permutation of can be
implemented as a composition of these gates. Since every bit operation that
does not use all of the bits performs an even permutation, we need to use at
least one auxiliary bit to perform every permutation, and it is known that one
bit is indeed enough. Without auxiliary bits, all even permutations can be
implemented. We generalize these results to non-binary logic: If is a
finite set of odd cardinality then a finite gate set can generate all
permutations of for all , without any auxiliary symbols. If the
cardinality of is even then, by the same argument as above, only even
permutations of can be implemented for large , and we show that indeed
all even permutations can be obtained from a finite universal gate set. We also
consider the conservative case, that is, those permutations of that
preserve the weight of the input word. The weight is the vector that records
how many times each symbol occurs in the word. It turns out that no finite
conservative gate set can, for all , implement all conservative even
permutations of without auxiliary bits. But we provide a finite gate set
that can implement all those conservative permutations that are even within
each weight class of .Comment: Submitted to Rev Comp 201
Recruitment Market Trend Analysis with Sequential Latent Variable Models
Recruitment market analysis provides valuable understanding of
industry-specific economic growth and plays an important role for both
employers and job seekers. With the rapid development of online recruitment
services, massive recruitment data have been accumulated and enable a new
paradigm for recruitment market analysis. However, traditional methods for
recruitment market analysis largely rely on the knowledge of domain experts and
classic statistical models, which are usually too general to model large-scale
dynamic recruitment data, and have difficulties to capture the fine-grained
market trends. To this end, in this paper, we propose a new research paradigm
for recruitment market analysis by leveraging unsupervised learning techniques
for automatically discovering recruitment market trends based on large-scale
recruitment data. Specifically, we develop a novel sequential latent variable
model, named MTLVM, which is designed for capturing the sequential dependencies
of corporate recruitment states and is able to automatically learn the latent
recruitment topics within a Bayesian generative framework. In particular, to
capture the variability of recruitment topics over time, we design hierarchical
dirichlet processes for MTLVM. These processes allow to dynamically generate
the evolving recruitment topics. Finally, we implement a prototype system to
empirically evaluate our approach based on real-world recruitment data in
China. Indeed, by visualizing the results from MTLVM, we can successfully
reveal many interesting findings, such as the popularity of LBS related jobs
reached the peak in the 2nd half of 2014, and decreased in 2015.Comment: 11 pages, 30 figure, SIGKDD 201
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Administration of Interleukin-15 Peptide Improves Cardiac Function in a Mouse Model of Myocardial Infarction.
Interleukin-15 is a pleotropic factor, capable of modulating metabolism, survival, proliferation, and differentiation in many different cell types. The rationale behind this study relates to previous work demonstrating that IL-15 is a major factor present in stem cell extracts, which protects cardiomyocytes subjected to hypoxic stress in vitro. The objective of this current study was to assess whether administration of IL-15 peptide will also show protective effects in vivo. The data indicate that administration of IL-15 reduces cell death, increases vascularity, decreases scar size, and significantly improves left ventricular ejection fraction in a mouse model of myocardial infarction
Plasmon Resonances in Nanoparticles, Their Applications to Magnetics and Relation to the Riemann Hypothesis
The review of the mathematical treatment of plasmon resonances as an
eigenvalue problem for specific boundary integral equations is presented and
general properties of plasmon spectrum are outlined. Promising applications of
plasmon resonances to magnetics are described. Interesting relation of
eigenvalue treatment of plasmon resonances to the Riemann hypothesis is
discussed.Comment: 10 pages; misprints corrected, some explanations added. Physica B
(2011
Theory of Dicke narrowing in coherent population trapping
The Doppler effect is one of the dominant broadening mechanisms in thermal
vapor spectroscopy. For two-photon transitions one would naively expect the
Doppler effect to cause a residual broadening, proportional to the wave-vector
difference. In coherent population trapping (CPT), which is a narrow-band
phenomenon, such broadening was not observed experimentally. This has been
commonly attributed to frequent velocity-changing collisions, known to narrow
Doppler-broadened one-photon absorption lines (Dicke narrowing). Here we show
theoretically that such a narrowing mechanism indeed exists for CPT resonances.
The narrowing factor is the ratio between the atom's mean free path and the
wavelength associated with the wave-vector difference of the two radiation
fields. A possible experiment to verify the theory is suggested.Comment: 6 pages, 2 figures; Introduction revise
Noncommutativity and Discrete Physics
The purpose of this paper is to present an introduction to a point of view
for discrete foundations of physics. In taking a discrete stance, we find that
the initial expression of physical theory must occur in a context of
noncommutative algebra and noncommutative vector analysis. In this way the
formalism of quantum mechanics occurs first, but not necessarily with the usual
interpretations. The basis for this work is a non-commutative discrete calculus
and the observation that it takes one tick of the discrete clock to measure
momentum.Comment: LaTeX, 23 pages, no figure
On-line construction of position heaps
We propose a simple linear-time on-line algorithm for constructing a position
heap for a string [Ehrenfeucht et al, 2011]. Our definition of position heap
differs slightly from the one proposed in [Ehrenfeucht et al, 2011] in that it
considers the suffixes ordered from left to right. Our construction is based on
classic suffix pointers and resembles the Ukkonen's algorithm for suffix trees
[Ukkonen, 1995]. Using suffix pointers, the position heap can be extended into
the augmented position heap that allows for a linear-time string matching
algorithm [Ehrenfeucht et al, 2011].Comment: to appear in Journal of Discrete Algorithm
The ideal energy of classical lattice dynamics
We define, as local quantities, the least energy and momentum allowed by
quantum mechanics and special relativity for physical realizations of some
classical lattice dynamics. These definitions depend on local rates of
finite-state change. In two example dynamics, we see that these rates evolve
like classical mechanical energy and momentum.Comment: 12 pages, 4 figures, includes revised portion of arXiv:0805.335
Clifford algebras and universal sets of quantum gates
In this paper is shown an application of Clifford algebras to the
construction of computationally universal sets of quantum gates for -qubit
systems. It is based on the well-known application of Lie algebras together
with the especially simple commutation law for Clifford algebras, which states
that all basic elements either commute or anticommute.Comment: 4 pages, REVTeX (2 col.), low-level language corrections, PR
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