1,832 research outputs found
Massless monopoles and the moduli space approximation
We investigate the applicability of the moduli space approximation in
theories with unbroken non-Abelian gauge symmetries. Such theories have
massless magnetic monopoles that are manifested at the classical level as
clouds of non-Abelian field surrounding one or more massive monopoles. Using an
SO(5) example with one massive and one massless monopole, we compare the
predictions of the moduli space approximation with the results of a numerical
solution of the full field equations. We find that the two diverge when the
cloud velocity becomes of order unity. After this time the cloud profile
approximates a spherical wavefront moving at the speed of light. In the region
well behind this wavefront the moduli space approximation continues to give a
good approximation to the fields. We therefore expect it to provide a good
description of the motion of the massive monopoles and of the transfer of
energy between the massive and massless monopoles.Comment: 18 pages, 5 figure
More on scattering of Chern-Simons vortices
I derive a general formalism for finding kinetic terms of the effective
Lagrangian for slowly moving Chern-Simons vortices. Deformations of fields
linear in velocities are taken into account. From the equations they must
satisfy I extract the kinetic term in the limit of coincident vortices. For
vortices passing one over the other there is locally the right-angle
scattering. The method is based on analysis of field equations instead of
action functional so it may be useful also for nonvariational equations in
nonrelativistic models of Condensed Matter Physics.Comment: discussion around Eq.(45) is generalised, one more condition for the
local right-angle scattering is adde
Modeling tidal current around Mokpo, the South Western coastal zone of Korea
This study provide modeling of tidal circulation around the Mokpo coastal zone (MC) using unstructured triangular horizontal grid by which high resolution is concentrated in the local region that reaches to 100 m. For this simulation, the 3D finite-volume ocean model FVCOM is applied for the numerical simulation. Only the astronomical tidal constituent M2 and its harmonic M4 are considered. By expanding open boundary to the shelf break of the East China Sea, only M2 elevation was specified on the open boundaries, and the generation of M4 tide around MC was observed, which is the representative criteria for the accuracy of the shallow water tide simulation. Around the intertidal zone of MC, wet/dry point treatment method incorporated in FVCOM was also used and tested its applicability in the level of resolution of this model
UB Online Courses: An On-Demand Video-Streaming Service for Online Education
Online education in the past few years has become a very convenient and cost-effective alternative to the traditional class-based education offered on college and university campuses. Its popularity can been seen in the increasing number of online courses being offered by many universities around the world; and the University of Bridgeport is no exception. To handle the increasing demand on online education programs, the current methods and technologies need to be improved to meet the student expectations of ease of use, accessibility and availability. In this work weâre addressing issues in the current online education services provided at UB, such as the standardization of video formats, making the lecture videos viewable on smart phone devices, and making all courses available in a central location
Good agricultural practices - food safety and animal welfare issues around egg powder exports from India
First and Second Order Vortex Dynamics
The low energy dynamics of vortices in selfdual Abelian Higgs theory is of
second order in vortex velocity and characterized by the moduli space metric.
When Chern-Simons term with small coefficient is added to the theory, we show
that a term linear in vortex velocity appears and can be consistently added to
the second order expression. We provides an additional check of the first and
second order terms by studying the angular momentum in the field theory. We
briefly explore other first order term due to small background electric charge
density and also the harmonic potential well for vortices given by the moment
of inertia.Comment: a rev tex file, 22 pages, no figur
Hyperbolic calorons, monopoles, and instantons
We construct families of SO(3)-symmetric charge 1 instantons and calorons on
the space H^3 x R. We show how the calorons include instantons and hyperbolic
monopoles as limiting cases. We show how Euclidean calorons are the flat space
limit of this family.Comment: 11 pages, no figures 1 reference added Published version available
at: http://www.springerlink.com/content/k0j4815u54303450
Mesh update techniques for free-surface flow solvers using spectral element method
This paper presents a novel mesh-update technique for unsteady free-surface
Newtonian flows using spectral element method and relying on the arbitrary
Lagrangian--Eulerian kinematic description for moving the grid. Selected
results showing compatibility of this mesh-update technique with spectral
element method are given
UK-based, multisite, prospective cohort study of small bowel obstruction in acute surgical services: National Audit of Small Bowel Obstruction (NASBO) protocol
Introduction Small bowel obstruction (SBO) is a common indication for emergency laparotomy in the UK, which is associated with a 90-day mortality rate of 13%. There are currently no UK clinical guidelines for the management of this condition. The aim of this multicentre prospective cohort study is to describe the burden, variation in management and associated outcomes of SBO in the UK adult population. Methods and analysis UK hospitals providing emergency general surgery are eligible to participate. This study has three components: (1) a clinical preference questionnaire to be completed by consultants providing emergency general surgical care to assesses preferences in diagnostics and therapeutic approaches, including laparoscopy and nutritional interventions; (2) site resource profile questionnaire to indicate ease of access to diagnostic services, operating theatres, nutritional support teams and postoperative support including intensive care; (3) prospective cohort study of all cases of SBO admitted during an 8-week period at participating trusts. Data on diagnostics, operative and nutritional interventions, and in-hospital mortality and morbidity will be captured, followed by data validation. Ethics and dissemination This will be conducted as a national audit of practice in conjunction with trainee research collaboratives, with support from patient representatives, surgeons, anaesthetists, gastroenterologists and a clinical trials unit. Site-specific reports will be provided to each participant site as well as an overall report to be disseminated through specialist societies. Results will be published in a formal project report endorsed by stakeholders, and in peer-reviewed scientific reports. Key findings will be debated at a focused national meeting with a view to quality improvement initiatives
Photon-Phonon-assisted tunneling through a single-molecular quantum dot
Based on exactly mapping of a many-body electron-phonon interaction problem
onto a one-body problem, we apply the well-established nonequilibrium Green
function technique to solve the time-dependent phonon-assisted tunneling at low
temperature through a single-molecular quantum dot connected to two leads,
which is subject to a microwave irradiation field. It is found that in the
presence of the electron-phonon interaction and the microwave irradiation
field, the time-average transmission and the nonlinear differential conductance
display additional peaks due to pure photon absorption or emission processes
and photon-absorption-assisted phonon emission processes. The variation of the
time-average current with frequency of the microwave irradiation field is also
studied.Comment: 9 pages, 6 figures, submitted to Phys. Rev. B. accepted by Phys. Rev.
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