Search results for "CONNECTION"
showing 10 items of 489 documents
Real class sizes and real character degrees
2010
Perhaps unexpectedly, there is a rich and deep connection between field of values of characters, their degrees and the structure of a finite group. Some of the fundamental results on the degrees of characters of finite groups, as the Ito–Michler and Thompson's theorems, admit a version involving only characters with certain fixed field of values ([DNT, NS, NST2, NT1, NT3]).
SmartCampus Project
2017
The aim of the SmartCampus project is to create an environment which enables high-quality, flexible and effective studying, both as traditional face-to-face and online. A focal result of the project is the CiNetCampus environment, developed in connection with the Master’s education in mathematical information technology. It increase flexibility in education with the help of video lectures and add interactivity to lecture videos. It was also possible to integrate other functionalities to the environment that are useful for teaching and studying. This paper focuses on the presentation of the CiNetCampus environment and the functionalities implemented for it. The paper also highlights the impa…
A new design problem in the formulation of a special moment resisting connection device for preventing local buckling
2021
In the present paper an improved formulation devoted to the optimal design problem of a special moment resisting connection device for steel frames is proposed. This innovative device is called a Limited Resistance Plastic Device (LRPD) and it has been recently proposed and patented by some of the authors. It is thought to be preferably located at the extremes of the beam, connecting the beam end cross section with the relevant column. The typical device is a steel element characterized by symmetry with respect to three orthogonal barycentric planes and constituted by a sequence of three portions with abrupt cross section changes. The main novelty of the present proposal is related to the d…
Ten Years of Paleoceanographic Studies at ODP Site 963 (Central Mediterranean Sea)
2014
The geographical location, the shape and the circulation pattern makes the Mediterranean Sea an ideal laboratory to study the interplay between different climatic systems, abrupt climate changes and the response of marine ecosystems. The Ocean Drilling Program Site 963 was drilled in the Northwestern part of the Sicily Channel, the sill that divides the western from the eastern Mediterranean Sea. Numerous papers have been published on Site 963 sediments in the last decade, investigating Mediterranean paleoceanographic themes. Here we offer a synthetic framework of these investigations carried out by sub-centennial resolution. We present the whole sequence of suborbital climatic oscillations…
An evaluation study on the embedding of reflective practice in the further education programme KigaDance for nursery teachers
2020
This article deals with the connection between theory and practice in the context of a further education programme (FEP) (KigaDance) for nursery teachers based on contemporary dance education. The ...
Decoupled Control Scheme of Grid-Connected Split-Source Inverters
2017
During the last few years, single-stage power conversion systems has undergone a fast evolution to replace the conventional two-stage architecture, which includes a front-end dc-dc boost converter (BC) and an output voltage source inverter (VSI) [1]. This evolution has grown up to improve the overall system performance in terms of reducing its size, weight, and complexity. Most of these single-stage topologies and their different modulation schemes have been reviewed in [1]. Among these different single-stage options, the split-source inverter (SSI), shown in Figure 1, has been recently proposed in [2] as a single-stage dc-ac power converter topology to overcome some demerits in the other s…
Renormalisation group improvement in the stochastic formalism
2019
We investigate compatibility between the stochastic infrared (IR) resummation of light test fields on inflationary spacetimes and renormalisation group running of the ultra-violet (UV) physics. Using the Wilsonian approach, we derive improved stochastic Langevin and Fokker-Planck equations which consistently include the renormalisation group effects. With the exception of stationary solutions, these differ from the naive approach of simply replacing the classical potential in the standard stochastic equations with the renormalisation group improved potential. Using this new formalism, we exemplify the IR dynamics with the Yukawa theory during inflation, illustrating the differences between …
Palatini Approach to Modified Gravity: f(R) Theories and Beyond
2011
We review the recent literature on modified theories of gravity in the Palatini approach. After discussing the motivations that lead to consider alternatives to Einstein's theory and to treat the metric and the connection as independent objects, we review several topics that have been recently studied within this framework. In particular, we provide an in-depth analysis of the cosmic speedup problem, laboratory and solar systems tests, the structure of stellar objects, the Cauchy problem, and bouncing cosmologies. We also discuss the importance of going beyond the f(R) models to capture other phenomenological aspects related with dark matter/energy and quantum gravity.
Renormalization group flow of the Holst action
2010
The renormalization group (RG) properties of quantum gravity are explored, using the vielbein and the spin connection as the fundamental field variables. The scale dependent effective action is required to be invariant both under space time diffeomorphisms and local frame rotations. The nonperturbative RG equation is solved explicitly on the truncated theory space defined by a three parameter family of Holst-type actions which involve a running Immirzi parameter. We find evidence for the existence of an asymptotically safe fundamental theory, probably inequivalent to metric quantum gravity constructed in the same way.
Geodesically complete BTZ-type solutions of $2+1$ Born-Infeld gravity
2016
We study Born-Infeld gravity coupled to a static, nonrotating electric field in $2+1$ dimensions and find exact analytical solutions. Two families of such solutions represent geodesically complete, and hence nonsingular, spacetimes. Another family represents a point-like charge with a singularity at the center. Despite the absence of rotation, these solutions resemble the charged, rotating BTZ solution of General Relativity but with a richer structure in terms of horizons. The nonsingular character of the first two families turn out to be attached to the emergence of a wormhole structure on their innermost region. This seems to be a generic prediction of extensions of General Relativity for…