96,344 research outputs found
Imperfection sensitivity of optimum structural designs for a Mars entry capsule
Analytical evaluation of buckling modes of shell configurations to determine imperfection sensitivity of optimum structural designs for Mars entry capsul
Scars on the CBR?
We ask whether the universe can be a patchwork consisting of distinct regions
of matter and antimatter. In previous work we demonstrated that
post-recombination matter-antimatter contact near regional boundaries leads to
an observable (but unobserved) gamma-ray flux for domain sizes of less than a
few thousand Mpc, thereby excluding such domains. In this paper we consider the
pre-recombination signal from domains of larger size.Comment: 6 pages, late
A solution to the fermion doubling problem for supersymmetric theories on the transverse lattice
Species doubling is a problem that infects most numerical methods that use a
spatial lattice. An understanding of species doubling can be found in the
Nielsen-Ninomiya theorem which gives a set of conditions that require species
doubling. The transverse lattice approach to solving field theories, which has
at least one spatial lattice, fails one of the conditions of the
Nielsen-Ninomiya theorem nevertheless one still finds species doubling for the
standard Lagrangian formulation of the transverse lattice. We will show that
the Supersymmetric Discrete Light Cone Quantization (SDLCQ) formulation of the
transverse lattice does not have species doubling.Comment: 4 pages, v2: a reference and comments added, the version to appear in
Phys. Rev.
Computer program for stress, vibration, and buckling characteristics of general shells of revolution
Structures Research Associates (SRA) system of programs is composed of six compatible computer programs for structural analyses of axisymmetric shell structures. Theories and methods upon which these programs are based are presented in documentation. They apply to a common structural model but analyze different modes of structural response
Local sequence features that influence AP-1 cis-regulatory activity
In the genome, most occurrences of transcription factor binding sites (TFBS) have no cis-regulatory activity, which suggests that flanking sequences contain information that distinguishes functional from nonfunctional TFBS. We interrogated the role of flanking sequences near Activator Protein 1 (AP-1) binding sites that reside in DNase I Hypersensitive Sites (DHS) and regions annotated as Enhancers. In these regions, we found that sequence features directly adjacent to the core motif distinguish high from low activity AP-1 sites. Some nearby features are motifs for other TFs that genetically interact with the AP-1 site. Other features are extensions of the AP-1 core motif, which cause the extended sites to match motifs of multiple AP-1 binding proteins. Computational models trained on these data distinguish between sequences with high and low activity AP-1 sites and also predict changes in cis-regulatory activity due to mutations in AP-1 core sites and their flanking sequences. Our results suggest that extended AP-1 binding sites, together with adjacent binding sites for additional TFs, encode part of the information that governs TFBS activity in the genome.</jats:p
Synthesis of distributed systems Annual report, 1 Sep. 1967 - 31 Aug. 1968
Synthesis of distributed systems with application to feedback networks for phase shift oscillator
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