1,883 research outputs found
p-Adic Path Integrals for Quadratic Actions
The Feynman path integral in p-adic quantum mechanics is considered. The
probability amplitude
for one-dimensional systems with quadratic actions is calculated in an exact
form, which is the same as that in ordinary quantum mechanics.Comment: 9 page
Education and Research in the SEENET-MTP Regional Framework for Higher Education in Physics
Southeastern European countries undergo significant changes in the
demand/supply ratio on the labour market and in the structure of professional
competences that are necessary for undertaking a professional activity. In
addition, brain-drain process and decrease of interest for a career in basic
sciences put many challenges for our community. Consequently, based on the
activity of the Southeastern European Network in Mathematical and Theoretical
Physics (SEENET MTP Network) in connecting groups and persons working in
mathematics and theoretical physics, we investigate specific qualifications
recognized in these fields in all the countries from the region, and the
related competences necessary for practicing the respective occupations. A list
of new possible occupations will be promoted for inclusion in the National
Qualifications Register for Higher Education. Finally, we analyze the vision
existing in this region on the higher education qualifications against the
European vision and experience, in particular in training of Master students,
PhD students, and senior teaching and research staff through the Network, i.e.
multilateral and bilateral programs.Comment: 6 pages, Talk given at 7th International Conference of the Balkan
Physical Union, Alexandruoplos, Greece, 9-13 September 2009. To be published
in AIP Conf.Pro
Zero Dimensional Field Theory of Tachyon Matter
The first issue about the object (now) called tachyons was published almost
one century ago. Even though there is no experimental evidence of tachyons
there are several reasons why tachyons are still of interest today, in fact
interest in tachyons is increasing. Many string theories have tachyons
occurring as some of the particles in the theory. In this paper we consider the
zero dimensional version of the field theory of tachyon matter proposed by A.
Sen. Using perturbation theory and ideas of S. Kar, we demonstrate how this
tachyon field theory can be connected with a classical mechanical system, such
as a massive particle moving in a constant field with quadratic friction. The
corresponding Feynman path integral form is proposed using a perturbative
method. A few promising lines for further applications and investigations are
noted.Comment: 2 pages, Talk presented at the 6th International Conference of Balkan
Physical Union - BPU6, Istanbul, Turkey, August 22-26. 200
High School Class for Gifted Pupils in Physics and Sciences and Pupils` Skills Measured by Standard and Pisa Test
The ``High school class for students with special abilities in physics`` was
founded in Nis, Serbia in 2003. The basic aim of this project has been
introducing a broadened curriculum of physics, mathematics, computer science,
as well as chemistry and biology. We present analysis of the pupils` skills in
solving rather problem oriented test, as PISA test, and compare their results
with the results of pupils who study under standard curricula. Analysis of
achievement data should clarify what are benefits of introducing in school
system track for gifted students. Additionally, item analysis helps in
understanding and improvement of learning strategies efficacy.Comment: 6 pages, Talk given at 7th International Conference of the Balkan
Physical Union, Alexandruoplos, Greece, 9-13 September 2009. To be published
in AIP Conf.Pro
Exact Site Percolation Thresholds Using the Site-to-Bond and Star-Triangle Transformations
I construct a two-dimensional lattice on which the inhomogeneous site
percolation threshold is exactly calculable and use this result to find two
more lattices on which the site thresholds can be determined. The primary
lattice studied here, the ``martini lattice'', is a hexagonal lattice with
every second site transformed into a triangle. The site threshold of this
lattice is found to be , while the others have and
. This last solution suggests a possible approach to establishing
the bound for the hexagonal site threshold, . To derive these
results, I solve a correlated bond problem on the hexagonal lattice by use of
the star-triangle transformation and then, by a particular choice of
correlations, solve the site problem on the martini lattice.Comment: 12 pages, 10 figures. Submitted to Physical Review
Validation of 2D shock capturing flood models around a surcharging manhole
This work offers a detailed validation of finite volume (FV) flood models in the case where horizontal floodplain flow is affected by sewer surcharge flow via a manhole. The FV numerical solution of the 2D shallow water equations is considered based on two approximate Riemann solvers, HLLC and Roe, on both quadrilateral structured and triangular unstructured mesh-types. The models are validated against a high resolution experimental data-set obtained using a physical model of a sewer system linked to a floodplain via a manhole. It was verified that the sensitivity of the models is inversely proportional to the surcharged flow/surface inflow ratio, and therefore requires more calibration from the user especially when concerned with localised modelling of sewer-to-floodplain flow. Our findings provide novel evidence that shock capturing FV-based flood models are applicable to simulate localised sewer-to-floodplain flow interaction
COST-S: a new methodology and tools for sewerage asset management based on whole life costs
This is the final version of the article. Freely available from IWA Publishing via the link in this record.This paper discusses the development of a methodology and software tools aimed at
assisting management decisions in order to provide acceptable performance at a
minimum cost over the whole life of the sewerage system. Whole Life Costing (WLC)
approaches have been shown to offer an ideal platform to provide investment and
operational management tools that take account of the timing of interventions, system
behaviour and performance all within a sensible economic and engineering framework.
The need for such a methodology and the requirements for its useful implementation
are introduced first. The paper then describes how research collaboration between the
UK Water Industry and two UK research centres (Centre for Water Systems at Exeter
University and Pennine Water Group at Universities of Sheffield and Bradford), and
supported by the UK Engineering and Physical Sciences Research Council grant,
resulted in an innovative, practical and auditable methodology with associated tools for
better proactive management of ageing and rapidly deteriorating sewerage systems.The authors would like to
acknowledge the generous support of
EPSRC (Project No.GR/M16122/01
and GR/R98617/01) as well as that of
the industrial collaborators;AWG,
Northumbrian Water,Thames Water
Services,United Utilities and Yorkshire
Water Services
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