6,786 research outputs found
Turchin's Relation for Call-by-Name Computations: A Formal Approach
Supercompilation is a program transformation technique that was first
described by V. F. Turchin in the 1970s. In supercompilation, Turchin's
relation as a similarity relation on call-stack configurations is used both for
call-by-value and call-by-name semantics to terminate unfolding of the program
being transformed. In this paper, we give a formal grammar model of
call-by-name stack behaviour. We classify the model in terms of the Chomsky
hierarchy and then formally prove that Turchin's relation can terminate all
computations generated by the model.Comment: In Proceedings VPT 2016, arXiv:1607.0183
RMS/Rate Dynamics via Localized Modes
We consider some reduction from nonlinear Vlasov-Maxwell equation to rms/rate
equations for second moments related quantities. Our analysis is based on
variational wavelet approach to rational (in dynamical variables)
approximation. It allows to control contribution from each scale of underlying
multiscales and represent solutions via multiscale exact nonlinear eigenmodes
(waveletons) expansions. Our approach provides the possibility to work with
well-localized bases in phase space and best convergence properties of the
corresponding expansions without perturbations or/and linearization procedures.Comment: 4 pages, 2 figures, JAC2001.cls, presented at European Particle
Accelerator Conference (EPAC02), Paris, June 3-7, 2002; changed from A4 to US
format for correct printin
Approximating solution structure of the Weighted Sentence Alignment problem
We study the complexity of approximating solution structure of the bijective
weighted sentence alignment problem of DeNero and Klein (2008). In particular,
we consider the complexity of finding an alignment that has a significant
overlap with an optimal alignment. We discuss ways of representing the solution
for the general weighted sentence alignment as well as phrases-to-words
alignment problem, and show that computing a string which agrees with the
optimal sentence partition on more than half (plus an arbitrarily small
polynomial fraction) positions for the phrases-to-words alignment is NP-hard.
For the general weighted sentence alignment we obtain such bound from the
agreement on a little over 2/3 of the bits. Additionally, we generalize the
Hamming distance approximation of a solution structure to approximating it with
respect to the edit distance metric, obtaining similar lower bounds
Classical and Quantum Ensembles via Multiresolution. II. Wigner Ensembles
We present the application of the variational-wavelet analysis to the
analysis of quantum ensembles in Wigner framework. (Naive) deformation
quantization, the multiresolution representations and the variational approach
are the key points. We construct the solutions of Wigner-like equations via the
multiscale expansions in the generalized coherent states or high-localized
nonlinear eigenmodes in the base of the compactly supported wavelets and the
wavelet packets. We demonstrate the appearance of (stable) localized patterns
(waveletons) and consider entanglement and decoherence as possible
applications.Comment: 5 pages, 2 figures, espcrc2.sty, Presented at IX International
Workshop on Advanced Computing and Analysis Techniques in Physics Research,
Section III "Simulations and Computations in Theoretical Physics and
Phenomenology", ACAT 2003, December, 2003, KEK, Tsukub
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