p-Adic and Adelic Harmonic Oscillator with Time-Dependent Frequency

The classical and quantum formalism for a p-adic and adelic harmonic oscillator with time-dependent frequency is developed, and general formulae for main theoretical quantities are obtained. In particular, the p-adic propagator is calculated, and the existence of a simple vacuum state as well as adelic quantum dynamics is shown. Space discreteness and p-adic quantum-mechanical phase are noted.Comment: 10 page

p-Adic and Adelic Free Relativistic Particle

We consider spectral problem for a free relativistic particle in p-adic and adelic quantum mechanics. In particular, we found p-adic and adelic eigenfunctions. Within adelic approach there exist quantum states that exhibit discrete structure of spacetime at the Planck scale.Comment: 9 page

A Method for Evaluating Local Scour Depth at Bridge Piers due to Debris Accumulation

This is the author accepted manuscript. The final version is available from Thomas Telford via the DOI in this record This paper introduces a novel method for evaluating the effect of debris accumulation on local scour depth at bridge piers. The concept of a debris factor is proposed to replace the current effective and equivalent pier width approaches that have been shown to overestimate debris-induced scour in many instances. The concept enables a simpler, more direct and realistic estimation of the change in local scour depth due to debris since it accounts for (i) debris length (streamwise), width (spanwise) and thickness (depth wise), and (ii) the influence of debris elevation in flow, i.e. is applicable for free-surface debris, submerged debris, or debris resting on the stream bed. The concept works with all existing local scour equations alongside other factors that influence scour depth such as flow angle of attack and pier shape. The mathematical model that underpins the proposed concept is derived through multiple linear regression on experimental data obtained at Exeter and elsewhere. The proposed method is shown to improve accuracy by at least 24% and 5% in comparison to the effective and equivalent pier width approaches, respectively. More importantly, the method is shown to be robust, providing highly consistent results with significantly less uncertainty.Engineering and Physical Sciences Research Council (EPSRC

On p-Adic Sector of Adelic String

We consider construction of Lagrangians which are candidates for p-adic sector of an adelic open scalar string. Such Lagrangians have their origin in Lagrangian for a single p-adic string and contain the Riemann zeta function with the d'Alembertian in its argument. In particular, we present a new Lagrangian obtained by an additive approach which takes into account all p-adic Lagrangians. The very attractive feature of this new Lagrangian is that it is an analytic function of the d'Alembertian. Investigation of the field theory with Riemann zeta function is interesting in itself as well.Comment: 10 pages. Presented at the 2nd Conf. on SFT and Related Topics, Moscow, April 2009. Submitted to Theor. Math. Phy

Experimental calibration and validation of sewer/surface flow exchange equations in steady and unsteady flow conditions

This is the final version of the article. Available from Elsevier via the DOI in this record.The linkage between sewer pipe flow and floodplain flow is recognised to induce an important source of uncertainty within two-dimensional (2D) urban flood models. This uncertainty is often attributed to the use of empirical hydraulic formulae (the one-dimensional (1D) weir and orifice steady flow equations) to achieve data-connectivity at the linking interface, which require the determination of discharge coefficients. Because of the paucity of high resolution localised data for this type of flows, the current understanding and quantification of a suitable range for those discharge coefficients is somewhat lacking. To fulfil this gap, this work presents the results acquired from an instrumented physical model designed to study the interaction between a pipe network flow and a floodplain flow. The full range of sewer-to-surface and surface-to-sewer flow conditions at the exchange zone are experimentally analysed in both steady and unsteady flow regimes. Steady state measured discharges are first analysed considering the relationship between the energy heads from the sewer flow and the floodplain flow; these results show that existing weir and orifice formulae are valid for describing the flow exchange for the present physical model, and yield new calibrated discharge coefficients for each of the flow conditions. The measured exchange discharges are also integrated (as a source term) within a 2D numerical flood model (a finite volume solver to the 2D Shallow Water Equations (SWE)), which is shown to reproduce the observed coefficients. This calibrated numerical model is then used to simulate a series of unsteady flow tests reproduced within the experimental facility. Results show that the numerical model overestimated the values of mean surcharge flow rate. This suggests the occurrence of additional head losses in unsteady conditions which are not currently accounted for within flood models calibrated in steady flow conditions.The research has been supported by the UK Engineering and Physical Sciences Research Council (grants ID: EP/K040405/1)

Hydrodynamic effects of debris blockage and scour on masonry bridges: towards experimental modelling

This paper describes the preliminary stage of an ongoing project investigating the hydrodynamic effects of debris blockage at masonry bridges. Debris blockage is cited as one of the primary causes of bridge failures in the UK and around the world. Masonry bridges, many of which are valuable historical assets, are particularly vulnerable to debris blockage due to their short spans and low clearance. This paper presents work done as part of the first phase of the project involving experimental research to understand the scientific relationships between debris characteristics and flow conditions. The study, being carried out at Centre for Water Systems at University of Exeter, utilizes a 0.6m-wide and 10m-long flume to run hydraulic experiments in order to characterize the impact of debris blockage on flow hydrodynamics, scour, and hydrodynamic pressures and forces at masonry bridges. This paper outlines the design of the experimental setup and the reasoning behind the choices for preliminary experimental parameters. The experiments are to include testing of bridge models and various 3D-printed debris shapes under realistic flow conditions. Geometry of the bridge and debris models are kept approximately similar to prototype conditions, with hydraulic conditions of the experiments designed to the degree that experimental constraints allow based on Froude similarity. Velocities, scour and hydrodynamic pressures are measured using an Acoustic Doppler Velocimeter, echo-sounding concept and pressure sensors, respectively. Preliminary results indicate that the designed experiments have the potential to enhance our understanding of the hydrodynamic effects of debris blockage

p-Adic Mathematical Physics

A brief review of some selected topics in p-adic mathematical physics is presented.Comment: 36 page

Towards device-size atomistic models of amorphous silicon

The atomic structure of amorphous materials is believed to be well described by the continuous random network model. We present an algorithm for the generation of large, high-quality continuous random networks. The algorithm is a variation of the "sillium" approach introduced by Wooten, Winer, and Weaire. By employing local relaxation techniques, local atomic rearrangements can be tried that scale almost independently of system size. This scaling property of the algorithm paves the way for the generation of realistic device-size atomic networks.Comment: 7 pages, 3 figure

Braided Tensor Products and the Covariance of Quantum Noncommutative Free Fields

We introduce the free quantum noncommutative fields as described by braided tensor products. The multiplication of such fields is decomposed into three operations, describing the multiplication in the algebra M of functions on noncommutative space-time, the product in the algebra H of deformed field oscillators, and the braiding by factor Psi_{M,H} between algebras M and H. For noncommutativity generated by the twist factor we shall employ the star-product realizations of the algebra M in terms of functions on standard Minkowski space. The covariance of single noncommutative quantum fields under deformed Poincare symmetries is described by the algebraic covariance conditions which are equivalent to the deformation of generalized Heisenberg equations on Poincare group manifold. We shall calculate the covariant braided field commutator, which for free quantum noncommutative fields provides the field quantization condition and is given by standard Pauli-Jordan function. For ilustration of our new scheme we present explicit calculations for the well-known case in the literature of canonically deformed free quantum fields.Comment: 19 pages, v.4, final versio

Balkans' Asteraceae Species as a Source of Biologically Active Compounds for the Pharmaceutical and Food Industry

Herbal drugs are a useful source of different bioactive compounds. Asteraceae species, as the most widespread vascular plants, can be used both as food and as medicine due to the great diversity of recorded chemical components - different phenolic compounds, terpenes, carotenoids, vitamins, alkaloids, etc. The Balkan Peninsula is characterized by great diversity of plants from Asteraceae family, including presence of rare and endemic species. In this review, results of the survey of chemical composition and biological activity, mainly focusing on antioxidant, antimicrobial and anticancer effects of selected Balkans' Asteraceae species were provided. In addition, information on edible plants from Asteraceae family is presented, due to growing interest for the so-called 'healthy diet' and possible application of Balkans' Asteraceae species as food of high nutritional value or as a source of functional food ingredients.This is peer-reviewed version of the following article: Kostić, A.; Janacković, P.; Kolasinac, S. M.; Dajić-Stevanović, Z. Balkans’ Asteraceae Species as a Source of Biologically Active Compounds for the Pharmaceutical and Food Industry. Chemistry & Biodiversity 2020, 17 (6). [https://doi.org/10.1002/cbdv.202000097