31,467 research outputs found

    A Formal, Resource Consumption-Preserving Translation of Actors to Haskell

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    We present a formal translation of an actor-based language with cooperative scheduling to the functional language Haskell. The translation is proven correct with respect to a formal semantics of the source language and a high-level operational semantics of the target, i.e. a subset of Haskell. The main correctness theorem is expressed in terms of a simulation relation between the operational semantics of actor programs and their translation. This allows us to then prove that the resource consumption is preserved over this translation, as we establish an equivalence of the cost of the original and Haskell-translated execution traces.Comment: Pre-proceedings paper presented at the 26th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2016), Edinburgh, Scotland UK, 6-8 September 2016 (arXiv:1608.02534

    Topology of evolving networks: local events and universality

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    Networks grow and evolve by local events, such as the addition of new nodes and links, or rewiring of links from one node to another. We show that depending on the frequency of these processes two topologically different networks can emerge, the connectivity distribution following either a generalized power-law or an exponential. We propose a continuum theory that predicts these two regimes as well as the scaling function and the exponents, in good agreement with the numerical results. Finally, we use the obtained predictions to fit the connectivity distribution of the network describing the professional links between movie actors.Comment: 13 pages, 3 figure

    Giant strongly connected component of directed networks

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    We describe how to calculate the sizes of all giant connected components of a directed graph, including the {\em strongly} connected one. Just to the class of directed networks, in particular, belongs the World Wide Web. The results are obtained for graphs with statistically uncorrelated vertices and an arbitrary joint in,out-degree distribution P(ki,ko)P(k_i,k_o). We show that if P(ki,ko)P(k_i,k_o) does not factorize, the relative size of the giant strongly connected component deviates from the product of the relative sizes of the giant in- and out-components. The calculations of the relative sizes of all the giant components are demonstrated using the simplest examples. We explain that the giant strongly connected component may be less resilient to random damage than the giant weakly connected one.Comment: 4 pages revtex, 4 figure

    Therapeutic evaluation of homeopathic treatment for canine oral papillomatosis

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    Aim: A study was conducted to evaluate the ameliorative potential of homeopathic drugs in combination (Sulfur 30C, Thuja 30C, Graphites 30C, and Psorinum 30C) in 16 dogs affected with oral papillomatosis which was not undergone any previous treatment. Materials and Methods: Dogs affected with oral papillomatosis, which have not undergone any initial treatment and fed with a regular diet. Dogs (total=16) were randomly divided into two groups, namely, homeopathic treatment group (n=8) and placebo control group (n=8). Random number table was used for allocation. Homeopathic combination of drugs and placebo drug (distilled water) was administered orally twice daily for 15 days. Clinical evaluation in both groups of dogs was performed by the same investigator throughout the period of study (12 months). Dogs were clinically scored for oral lesions on days 0, 5, 7, 10, 15, 20, 25, 30, 45, 60, 90, 120, and 150 after initiation of treatment. Results: The homeopathic treatment group showed early recovery with a significant reduction in oral lesions reflected by clinical score (p<0.001) in comparison to placebo-treated group. Oral papillomatous lesions regressed in the homeopathic group between 7 and 15 days, whereas regression of papilloma in the placebo group occurred between 90 and 150 days. The homeopathic treated group was observed for 12 months post-treatment period and no recurrence of oral papilloma was observed. Conclusion: The current study proves that the combination of homeopathy drugs aids in fastening the regression of canine oral papilloma and proved to be safe and cost-effective

    Bose-Einstein condensation in complex networks

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    The evolution of many complex systems, including the world wide web, business and citation networks is encoded in the dynamic web describing the interactions between the system's constituents. Despite their irreversible and non-equilibrium nature these networks follow Bose statistics and can undergo Bose-Einstein condensation. Addressing the dynamical properties of these non-equilibrium systems within the framework of equilibrium quantum gases predicts that the 'first-mover-advantage', 'fit-get-rich' and 'winner-takes-all' phenomena observed in competitive systems are thermodynamically distinct phases of the underlying evolving networks

    Search in weighted complex networks

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    We study trade-offs presented by local search algorithms in complex networks which are heterogeneous in edge weights and node degree. We show that search based on a network measure, local betweenness centrality (LBC), utilizes the heterogeneity of both node degrees and edge weights to perform the best in scale-free weighted networks. The search based on LBC is universal and performs well in a large class of complex networks.Comment: 14 pages, 5 figures, 4 tables, minor changes, added a referenc

    Multimode optomechanical system in the quantum regime

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    We realise a simple and robust optomechanical system with a multitude of long-lived (Q>107Q>10^7) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry-Perot resonator detects these modes' motion with a measurement rate (96 kHz96~\mathrm{kHz}) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures (10 K10\,\mathrm{K}). Reaching this quantum regime entails, i.~a., quantum measurement backaction exceeding thermal forces, and thus detectable optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for detection losses) and bandwidths ≲90 kHz\lesssim 90\,\mathrm{ kHz}. The multi-mode nature of the employed membrane and Fabry-Perot resonators lends itself to hybrid entanglement schemes involving multiple electromagnetic, mechanical, and spin degrees of freedom.Comment: 19 pages, 9 figure

    Collective strong coupling between ion Coulomb crystals and an optical cavity field: Theory and experiment

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    A detailed description and theoretical analysis of experiments achieving coherent coupling between an ion Coulomb crystal and an optical cavity field are presented. The various methods used to measure the coherent coupling rate between large ion Coulomb crystals in a linear quadrupole radiofrequency ion trap and a single field mode of a moderately high-finesse cavity are described in detail. Theoretical models based on a semiclassical approach are applied in assessment of the experimental results of [P. F. Herskind et al., Nature Phys. 5, 494 (2009)] and of complementary new measurements. Generally, a very good agreement between theory and experiments is obtained.Comment: 15 pages, 15 figure

    Modulated Scale-free Network in the Euclidean Space

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    A random network is grown by introducing at unit rate randomly selected nodes on the Euclidean space. A node is randomly connected to its ii-th predecessor of degree kik_i with a directed link of length ℓ\ell using a probability proportional to kiℓαk_i \ell^{\alpha}. Our numerical study indicates that the network is Scale-free for all values of α>αc\alpha > \alpha_c and the degree distribution decays stretched exponentially for the other values of α\alpha. The link length distribution follows a power law: D(ℓ)∼ℓδD(\ell) \sim \ell^{\delta} where δ\delta is calculated exactly for the whole range of values of α\alpha.Comment: 4 pages, 4 figures. To be published in Physical Review
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