We consider the expressive power of a general form of higher-order algebraic specification which allows constructors and hidden sorts and operations. We prove a completeness theorem which exactly characterises the exp...
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We consider the expressive power of a general form of higher-order algebraic specification which allows constructors and hidden sorts and operations. We prove a completeness theorem which exactly characterises the expressiveness of such specifications with respect to the analytical hierarchy. In particular we show that for any countable signature Sigma and minimal Sigma algebra A, A has complexity Pi(1)(1) if, and only if, A has a recursive second-order equational specification with constructors and hidden sorts and operators under higher-order initial semantics. (C) 1997 Academic Press.
The emergence of the "internet plus" era marks a significant gap in sports education for higher level training, which has laid the groundwork for mixed teaching. This article briefly discusses "the inte...
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The emergence of the "internet plus" era marks a significant gap in sports education for higher level training, which has laid the groundwork for mixed teaching. This article briefly discusses "the internet plus" and artificial intelligence mixed learning principles. This article introduces a problem-based Cognitive Reasoning Sports Teaching Model (CRSTM) designed to provide a transitory response to dynamic trails according to research theory and observations in teaching computer based sports learning techniques. computational mathematics training typically starts with identifying behavior expectations or anticipated performance. The field of educational psychology has long been receptive to the desirability of setting educational goals. Motor skill training is focused primarily on a set of options to incorporate critical task components. Human-Computer Interaction System for Education makes students and scholars learn about human features and acquire the skills essential to investigate people's interactions with and around technologies.
This paper considers generic load-balancing algorithms which efficiently parallelize a large class of applications based on traversing implicitly defined trees with irregular shape. First, a previous model is generali...
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This paper considers generic load-balancing algorithms which efficiently parallelize a large class of applications based on traversing implicitly defined trees with irregular shape. First, a previous model is generalized yielding tree-shaped computations which cover the cost for communication and problem splitting, a measure of granularity and an easy to quantify parameter which limits irregularity. Then the random polling load-balancing algorithm is analyzed yielding upper bounds which match lower bounds for a large class of possible algorithms and machines. These bounds even hold for a fully asynchronous communication model which is important for practically efficient implementations. Then, with poll-and-shuffle, an asymptotically even more efficient algorithm is introduced. By using predominantly local communications, it increases the usable communication bandwidth on hypercubic networks and meshes by a logarithmic factor. These analytic results are complemented by practical refinements and implementation results which successfully apply a portable and reusable library on machines with up to 1024 processors.
The Delaunay tree is a hierarchical data structure which is defined from the Delaunay triangulation and, roughly speaking, represents a triangulation as a hierarchy of balls. It allows a semidynamic construction of th...
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The Delaunay tree is a hierarchical data structure which is defined from the Delaunay triangulation and, roughly speaking, represents a triangulation as a hierarchy of balls. It allows a semidynamic construction of the Delaunay triangulation of a finite set of n points in any dimension. In this paper, we prove that a randomized construction of the Delaunay tree (and, thus, of the Delaunay triangulation) can be done in O(n log n) expected time in the plane and in O(n[d/2]) expected time in d-dimensional space. These results are optimal for fixed d. The algorithm is extremely simple and experimental results are given.
Direct unequal C-H bond difunctionalization of phosphorylated diamantane was achieved in high yield from the corresponding phosphonates. Reduction of the functionalized phosphonates provides access to novel primary an...
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Direct unequal C-H bond difunctionalization of phosphorylated diamantane was achieved in high yield from the corresponding phosphonates. Reduction of the functionalized phosphonates provides access to novel primary and secondary alkyl/aryl diamantane phosphines. The prepared primary diamantyl phosphines are quite air stable compared to their adamantyl and especially alkyl or aryl analogues. This finding is corroborated by comparing the singly occupied molecular orbital energy levels of the corresponding phosphine radical cations obtained by density functional theorycomputations.
We present yadism, a library for the evaluation of both polarized and unpolarized deep-inelastic scattering (DIS) structure functions and cross sections up to N3\documentclass[12pt]{minimal} \usepackage{amsmath} \usep...
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We present yadism, a library for the evaluation of both polarized and unpolarized deep-inelastic scattering (DIS) structure functions and cross sections up to N3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{3}$$\end{document}LO in perturbative QCD. The package provides computations of observables in fixed-flavor and zero-mass variable flavor number schemes. The implementation of the general mass variable flavor number schemes is supported through the high virtuality limits for the heavy flavor coefficients. In addition, yadism provides a set of tools for the generation of interpolation grids in the PDF-independent PineAPPL format, allowing to test the PDF dependence on any DIS observable without needing to rerun the computation. This work is part of an ongoing effort to standardize the format of theory predictions in high-energy physics within the pineline framework. The code is open source, written in Python and documented to facilitate usage, integrations, and further extensions. Finally, the code has been benchmarked against the widely used APFEL++ and QCDNUM libraries.
Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are develo...
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Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are developed to enable application of pySecDec (a Python-language-based package designed for numerical calculation of dimensionally-regulated loop integrals) to numerically evaluate finite-temperature loop integrals in the imaginary time (Matsubara) formalism. These methods consist of two main elements: an inverse Wick rotation that converts a finite-temperature loop integral into a form applicable to pySecDec, and asymptotic techniques to regulate and accelerate convergence of the Matsubara frequency summations. Numerical pySecDec evaluation of finite-temperature, two-point and three-point, one-loop topologies for scalar fields is used to illustrate and validate these new methodologies. Advantages of these finite-temperature pySecDec numerical methods are illustrated by the inclusion of multiple mass and external momentum scales.
The optimization of radio frequency-wave (RF) systems for fusion experiments is often performed using ray-tracing codes, which rely on the geometrical-optics (GO) approximation. However, GO fails at caustics such as c...
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The optimization of radio frequency-wave (RF) systems for fusion experiments is often performed using ray-tracing codes, which rely on the geometrical-optics (GO) approximation. However, GO fails at caustics such as cutoffs and focal points, erroneously predicting the wave intensity to be infinite. This is a critical shortcoming of GO, since the caustic wave intensity is often the quantity of interest, e.g., RF heating. Full-wave modeling can be used instead, but the computational cost limits the speed at which such optimizations can be performed. We have developed a less expensive alternative called metaplectic geometrical optics (MGO). Instead of evolving waves in the usual x (coordinate) or k (spectral) representation, MGO uses a mixed X equivalent to A x + B k representation. By continuously adjusting the matrix coefficients A and B along the rays, one can ensure that GO remains valid in the X coordinates without caustic singularities. The caustic-free result is then mapped back onto the original x space using metaplectic transforms. Here, we overview the MGO theory and review algorithms that will aid the development of an MGO-based ray-tracing code. We show how using orthosymplectic transformations leads to considerable simplifications compared to previously published MGO formulas. We also prove explicitly that MGO exactly reproduces standard GO when evaluated far from caustics (an important property that until now has only been inferred from numerical simulations), and we relate MGO to other semiclassical caustic-removal schemes published in the literature. This discussion is then augmented by an explicit comparison of the computed spectrum for a wave bounded between two cutoffs. Published under an exclusive license by AIP Publishing.
This review covers most recent advances in computation of F-19 NMR chemical shifts and spin-spin coupling constants involving F-19 nucleus calculated at different levels of theory. It deals mainly with electronic and ...
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This review covers most recent advances in computation of F-19 NMR chemical shifts and spin-spin coupling constants involving F-19 nucleus calculated at different levels of theory. It deals mainly with electronic and stereochemical effects influencing these parameters, with a special emphasis on practical applications of such calculations. For F-19 NMR chemical shifts, a good deal of attention is focused on less common solid state studies, in addition to much more popular liquid state data. For spin-spin coupling constants, the main interest is concentrated on the most popular F-19 - H-1, F-19-C-13 and F-19 - F-19 couplings providing marked stereochemical behaviour. The bibliography includes 149 references. The bibliography includes 149 references. In memory of Professor Ruben Horacio Contreras, to commemorate his achievements in the field of theoretical and computational F-19 NMR.
Stochastic resonance (SR) occurs in bistable nonlinear systems subject to noise, as the entrainment of their output by a weak periodic modulation added to the input. Electronic computation involves switching of memory...
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Stochastic resonance (SR) occurs in bistable nonlinear systems subject to noise, as the entrainment of their output by a weak periodic modulation added to the input. Electronic computation involves switching of memory elements between two slates that correspond to 1 and 0, respectively, The possibility of switching errors due to SR in memory elements is considered, showing that it represents a negligible danger to reliable computation. (C) 1997 American Institute of Physics.
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