50,751 research outputs found
Fast systematic encoding of multiplicity codes
We present quasi-linear time systematic encoding algorithms for multiplicity
codes. The algorithms have their origins in the fast multivariate interpolation
and evaluation algorithms of van der Hoeven and Schost (2013), which we
generalise to address certain Hermite-type interpolation and evaluation
problems. By providing fast encoding algorithms for multiplicity codes, we
remove an obstruction on the road to the practical application of the private
information retrieval protocol of Augot, Levy-dit-Vehel and Shikfa (2014)
A new Truncated Fourier Transform algorithm
Truncated Fourier Transforms (TFTs), first introduced by Van der Hoeven,
refer to a family of algorithms that attempt to smooth "jumps" in complexity
exhibited by FFT algorithms. We present an in-place TFT whose time complexity,
measured in terms of ring operations, is comparable to existing not-in-place
TFT methods. We also describe a transformation that maps between two families
of TFT algorithms that use different sets of evaluation points.Comment: 8 pages, submitted to the 38th International Symposium on Symbolic
and Algebraic Computation (ISSAC 2013
Change of basis for m-primary ideals in one and two variables
Following recent work by van der Hoeven and Lecerf (ISSAC 2017), we discuss
the complexity of linear mappings, called untangling and tangling by those
authors, that arise in the context of computations with univariate polynomials.
We give a slightly faster tangling algorithm and discuss new applications of
these techniques. We show how to extend these ideas to bivariate settings, and
use them to give bounds on the arithmetic complexity of certain algebras.Comment: In Proceedings ISSAC'19, ACM, New York, USA. See proceedings version
for final formattin
C627
Gustaaf A. van der Hoeven, Energy efficient landscaping, Kansas State University, November 1982
C568
Gustaaf A. van der Hoeven, Landscaping the farmstead, Kansas State University, December 1983
The role of antiphase boundaries during ion sputtering and solid phase epitaxy of Si(001)
The Si(001) surface morphology during ion sputtering at elevated temperatures
and solid phase epitaxy following ion sputtering at room temperature has been
investigated using scanning tunneling microscopy. Two types of antiphase
boundaries form on Si(001) surfaces during ion sputtering and solid phase
epitaxy. One type of antiphase boundary, the AP2 antiphase boundary,
contributes to the surface roughening. AP2 antiphase boundaries are stable up
to 973K, and ion sputtering and solid phase epitaxy performed at 973K result in
atomically flat Si(001) surfaces.Comment: 16 pages, 4 figures, to be published in Surface Scienc
Virulence behavior of uropathogenic Escherichia coli strains in the host model Caenorhabditis elegans
Urinary tract infections (UTIs) are among the most common bacterial infections in humans. Although a number of bacteria can cause UTIs, most cases are due to infection by uropathogenic Escherichia coli (UPEC). UPEC are a genetically heterogeneous group that exhibit several virulence factors associated with colonization and persistence of bacteria in the urinary tract. Caenorhabditis elegans is a tiny, free-living nematode found worldwide. Because many biological pathways are conserved in C. elegans and humans, the nematode has been increasingly used as a model organism to study virulence mechanisms of microbial infections and innate immunity. The virulence of UPEC strains, characterized for antimicrobial resistance, pathogenicity-related genes associated with virulence and phylogenetic group belonging was evaluated by measuring the survival of C. elegans exposed to pure cultures of these strains. Our results showed that urinary strains can kill the nematode and that the clinical isolate ECP110 was able to efficiently colonize the gut and to inhibit the host oxidative response to infection. Our data support that C. elegans, a free-living nematode found worldwide, could serve as an in vivo model to distinguish, among uropathogenic E. coli, different virulence behavior
Towards a Model Theory for Transseries
The differential field of transseries extends the field of real Laurent
series, and occurs in various context: asymptotic expansions, analytic vector
fields, o-minimal structures, to name a few. We give an overview of the
algebraic and model-theoretic aspects of this differential field, and report on
our efforts to understand its first-order theory.Comment: Notre Dame J. Form. Log., to appear; 33 p
- …