9,468 research outputs found
Spacetime Defects: von K\'arm\'an vortex street like configurations
A special arrangement of spinning strings with dislocations similar to a von
K\'arm\'an vortex street is studied. We numerically solve the geodesic
equations for the special case of a test particle moving along twoinfinite rows
of pure dislocations and also discuss the case of pure spinning defects.Comment: 9 pages, 2figures, CQG in pres
Community building and virtual teamwork in an online learning environment
In the world of OTIS, an online Internet School for occupational therapists, students from four European countries were encouraged to work collaboratively through problem based learning by interacting with each other in a virtual semi-immersive environment. This paper aims to explore the issues that there was little interaction between students from different tutorial groups and virtual teamwork developed in each of the cross cultural tutorial groups. Synchronous data from European students was captured during tutorial sessions and peer booked meetings and evidence suggests that communities of interest were established. It is possible to conclude that collaborative systems can be designed, which encourage students to build trust and teamwork in a cross cultural online learning environment. </p
Possible Detection of Causality Violation in a Non-local Scalar Model
We consider the possibility that there may be causality violation detectable
at higher energies. We take a scalar nonlocal theory containing a mass scale
as a model example and make a preliminary study of how the causality
violation can be observed. We show how to formulate an observable whose
detection would signal causality violation. We study the range of energies
(relative to ) and couplings to which the observable can be used.Comment: Latex, 30 page
Limit Pricing and Predation in the Antitrust Laws: Economic and Legal Aspects
The overwhelming view in the economic literature is that limit pricing, the practice of establishing a non-profit-maximizing price with the intention of deterring entry of others into the market, either does not make economic sense or, in any event, does not have anticompetitive effects. This article will take a systematic look at the legal status of the limit price doctrine and propose its proper role
Visibility diagrams and experimental stripe structure in the quantum Hall effect
We analyze various properties of the visibility diagrams that can be used in
the context of modular symmetries and confront them to some recent experimental
developments in the Quantum Hall Effect. We show that a suitable physical
interpretation of the visibility diagrams which permits one to describe
successfully the observed architecture of the Quantum Hall states gives rise
naturally to a stripe structure reproducing some of the experimental features
that have been observed in the study of the quantum fluctuations of the Hall
conductance. Furthermore, we exhibit new properties of the visibility diagrams
stemming from the structure of subgroups of the full modular group.Comment: 8 pages in plain TeX, 7 figures in a single postscript fil
A spatial multi-criteria model for the evaluation of land redistribution plans
A planning support system for land consolidation has been developed that has, at its heart, an expert system called LandSpaCES (Land Spatial Consolidation Expert System) which contains a "design module" that generates alternative land redistributions under different scenarios and an "evaluation module" which integrates GIS with multi-criteria decision making for assessing these alternatives. This paper introduces the structural framework of the latter module which has been applied using a case study in Cyprus. Two new indices are introduced: the "parcel concentration coefficient" for measuring the dispersion of parcels; and the "landowner satisfaction rate" for predicting the acceptance of the land redistribution plan by the landowners in terms of the location of their new parcels. These two indices are used as criteria for the evaluation of the land redistribution alternatives and are transferable to any land consolidation project. Moreover, a modified version of the ratio estimation procedure, referred to as the "qualitative rating method" for assigning weights to the evaluation criteria, is presented, along with a set of non-linear value functions for standardizing the performance scores of the alternatives and incorporating expert knowledge for five evaluation criteria. The application of the module showed that it is a powerful new tool for the evaluation of alternative land redistribution plans that could be implemented in other countries after appropriate adjustments. A broader contribution has also been made to spatial planning processes, which might follow the methodology and innovations presented in this paper
LandParcelS: A module for automated land partitioning
Land fragmentation is a widespread problem and schemes for consolidating land are required to improve agricultural efficiency. This paper explains the development of a module called LandParcelS (Land Parcelling System) that is part of an integrated planning and decision support system called LAONISS which is being developed to assist land consolidation planning in Cyprus. LandParcelS is the component of the system that automates the land partitioning process by optimising land parcels in terms of shape, size and value. The methodology employs a genetic algorithm and results are presented when treating the partitioning task as either a single or multi-objective problem
Understanding of the Renormalization Program in a mathematically Rigorous Framework and an Intrinsic Mass Scale
we show there exists a mathematically consistent framework in which the
Renormalization Program can be understood in a natural manner. The framework
does not require any violations of mathematical rigor usually associated with
the Renormalization program. We use the framework of the non-local field
theories [these carry a finite mass scale (\Lambda)]and set up a finite
perturbative program. We show how this program leads to the perturbation series
of the usual renormalization program [except one difference] if the series is
restructured .We further show that the comparison becomes possible if there
exists a finite mass scale (\Lambda), with certain properties, in the Quantum
Field theory [which we take to be the scale present in the nonlocal theory]. We
give a way to estimate the scale (\Lambda). We also show that the finite
perturbation program differs from the usual renormalization program by a term;
which we propose can also be used to put a bound on (\Lambda).Comment: 19 pages, a missing equation added,a reference added and a few typos
correcte
- …