Modification of Newton's law of gravity at very large distances

We discuss a Modified Field Theory (MOFT) in which the number of fields can vary. It is shown that when the number of fields is conserved MOFT reduces to the standard field theory but interaction constants undergo an additional renormalization and acquire a dependence on spatial scales. In particular, the renormalization of the gravitational constant leads to the deviation of the law of gravity from the Newtons law in some range of scales $r_{min} r_{max}$ acquires a new constant value $G^{prime}sim Gr_{max}/r_{min}$. From the dynamical standpoint this looks as if every point source is surrounded with a halo of dark matter. It is also shown that if the maximal scale $r_{max}$ is absent, the homogeneity of the dark matter in the Universe is consistent with a fractal distribution of baryons in space, in which the luminous matter is located on thin two-dimensional surfaces separated by empty regions of ever growing size

Interaction of agents and environments

A new abstract model of interaction between agents and environments considered as objects of different types is introduced. Agents are represented by means of labelled transition systems considered up to bisimilarity. The equivalence of agents is characterised in terms of an algebra of behaviours which is a continuous algebra with approximation and two operations: nondeterministic choice and prefixing. Environments are introduced as agents supplied with an insertion function which takes the behaviour of an agent and the behaviour of an environment as arguments and returns the new behaviour of an environment. Arbitrary continuous functions can be used as insertion functions, and we use functions defined by means of rewriting logic as computable ones. The transformation of environment behaviours defined by the insertion function also defines a new type of agent equivalence--- insertion equivalence. Two behaviours are insertion equivalent if they define the same transformation of an environment. The properties of this equivalence are studied. Three main types of insertion functions are used to develop interesting applications: one-step insertion, head insertion, and look-ahead insertion functions

Corrections to the Newton and Coulomb potentials caused by effects of spacetime foam

We use an extended quantum field theory (EQFT) hep-th/9911168 to explore possible observational effects of the spacetime. It is shown that as it was expected the spacetime foam can provide quantum bose fields with a cutoff at very small scales, if the energy of zero - point fluctuations of fields is taken into account. It is also shown that EQFT changes the behaviour of massless fields at very large scales (in the classical region). We show that as $rgg 1/mu$ the Coulomb and Newton forces acquire the behaviour $sim 1/r$ (instead of $1/r^{2}$)

A general theory of action languages

We present a general theory of action-based languages as a paradigm, for the description, of those computational systems which include elements of concurrency and networking, and extend this approach to describe dist.ributed systems and also t,o describe the interaction of a system, with an environment. As part of this approach we introduce the Action Language as a common model for the class of nondeterministic concurrent programming languages and define its intensional and interaction semantics in terrors of continuous transformation of environment behavior. This semantics i.s specialized for programs with stores, and extended to describe distributed computations

The role of large-scale energy storage design and dispatch in the power grid: A study of very high grid penetration of variable renewable resources

We present a result of hourly simulation performed using hourly load data and the corresponding simulated output of wind and solar technologies distributed throughout the state of California. We examined how we could achieve very high-energy penetration from intermittent renewable system into the electricity grid. This study shows that the maximum threshold for the storage need is significantly less than the daily average demand. In the present study, we found that the approximate network energy storage is of the order of 186. GW. h/22. GW (approximately 22% of the average daily demands of California). Allowing energy dumping was shown to increase storage use, and by that way, increases grid penetration and reduces the required backup conventional capacity requirements. Using the 186. GW. h/22. GW storage and at 20% total energy loss, grid penetration was increased to approximately 85% of the annual demand of the year while also reducing the conventional backup capacity requirement to 35. GW. This capacity was sufficient to supply the year round hourly demand, including 59 GW peak demand, plus a distribution loss of about 5.3%. We conclude that designing an efficient and least cost grid may require the capability to capture diverse physical and operational policy scenarios of the future grid. © 2014 Elsevier Ltd

Convergence to equilibrium for many particle systems

The goal of this paper is to give a short review of recent results of the authors concerning classical Hamiltonian many particle systems. We hope that these results support the new possible formulation of Boltzmann's ergodicity hypothesis which sounds as follows. For almost all potentials, the minimal contact with external world, through only one particle of $N$, is sufficient for ergodicity. But only if this contact has no memory. Also new results for quantum case are presented

Effects of intervention with the SAFE strategy on trachoma across Ethiopia.

BACKGROUND/AIMS: The impact of the SAFE strategy (surgery, antibiotics, face washing, environmental hygiene), recommended to eliminate blinding trachoma, is not well explored. We determined the operational effectiveness of the whole SAFE intervention package. METHODS: Analytical cross-sectional trachoma surveys were conducted in four program areas across Ethiopia before and after 3 years of intervention with the SAFE strategy. A total of 8358 children 1-9 years, 4684 people above 14 and 3572 households were assessed in the follow-up evaluations using methodologies recommended by the WHO. Effects were measured by comparing follow-up proportions with baseline estimates of four key indicators. RESULTS: Coverage was 36% for trichiasis surgery, 59% for antibiotic and 57% for health-promotion services. Prevalence of trachoma trichiasis (TT) decreased from 4.6% (95% CI: 3.6% to 5.8%) down to 2.9% (CI: 2.1% to 3.9%). Prevalence of trachoma inflammation-follicular (TF) dropped from 36.7% (33.9% to 39.6%) to 18.4% (CI: 15.4% to 21.8%). The proportion of unclean faces and households not using latrines fell from 72.8% (68.9% to 76.4%) and 74.5% (69.9% to 78.7%) down to 47.0% (CI: 43% to 51%) and 51.7% (47.2% to 56.2%), respectively. All the reductions related with antibiotic (TF), face washing (clean face) and environmental (latrine) components were statistically significant except for Surgery (TT). CONCLUSIONS: Considerable decline in the magnitude of trachoma and its risk factors was observed in areas where the SAFE strategy was implemented. The coverage of services should be maintained or improved in order to eliminate blinding trachoma by the year 2020

Running a Production Grid Site at the London e-Science Centre

This paper describes how the London e-Science Centre cluster MARS, a production 400+ Opteron CPU cluster, was integrated into the production Large Hadron Collider Compute Grid. It describes the practical issues that we encountered when deploying and maintaining this system, and details the techniques that were applied to resolve them. Finally, we provide a set of recommendations based on our experiences for grid software development in general that we believe would make the technology more accessible. © 2006 IEEE

Helicity at Photospheric and Chromospheric Heights

In the solar atmosphere the twist parameter $\alpha$ has the same sign as magnetic helicity. It has been observed using photospheric vector magnetograms that negative/positive helicity is dominant in the northern/southern hemisphere of the Sun. Chromospheric features show dextral/sinistral dominance in the northern/southern hemisphere and sigmoids observed in X-rays also have a dominant sense of reverse-S/forward-S in the northern/southern hemisphere. It is of interest whether individual features have one-to-one correspondence in terms of helicity at different atmospheric heights. We use UBF \Halpha images from the Dunn Solar Telescope (DST) and other \Halpha data from Udaipur Solar Observatory and Big Bear Solar Observatory. Near-simultaneous vector magnetograms from the DST are used to establish one-to-one correspondence of helicity at photospheric and chromospheric heights. We plan to extend this investigation with more data including coronal intensities.Comment: 5 pages, 1 figure, 1 table To appear in "Magnetic Coupling between the Interior and the Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200