Quantum wire with periodic serial structure

Electron wave motion in a quantum wire with periodic structure is treated by direct solution of the Schrödinger equation as a mode-matching problem. Our method is particularly useful for a wire consisting of several distinct units, where the total transfer matrix for wave propagation is just the product of those for its basic units. It is generally applicable to any linearly connected serial device, and it can be implemented on a small computer. The one-dimensional mesoscopic crystal recently considered by Ulloa, Castaño, and Kirczenow [Phys. Rev. B 41, 12 350 (1990)] is discussed with our method, and is shown to be a strictly one-dimensional problem. Electron motion in the multiple-stub T-shaped potential well considered by Sols et al. [J. Appl. Phys. 66, 3892 (1989)] is also treated. A structure combining features of both of these is investigated

Quantum wire with periodic serial structure

Electron wave motion in a quantum wire with periodic structure is treated by direct solution of the Schrödinger equation as a mode-matching problem. Our method is particularly useful for a wire consisting of several distinct units, where the total transfer matrix for wave propagation is just the product of those for its basic units. It is generally applicable to any linearly connected serial device, and it can be implemented on a small computer. The one-dimensional mesoscopic crystal recently considered by Ulloa, Castaño, and Kirczenow [Phys. Rev. B 41, 12 350 (1990)] is discussed with our method, and is shown to be a strictly one-dimensional problem. Electron motion in the multiple-stub T-shaped potential well considered by Sols et al. [J. Appl. Phys. 66, 3892 (1989)] is also treated. A structure combining features of both of these is investigated.

Communication in networks with hierarchical branching

We present a simple model of communication in networks with hierarchical branching. We analyze the behavior of the model from the viewpoint of critical systems under different situations. For certain values of the parameters, a continuous phase transition between a sparse and a congested regime is observed and accurately described by an order parameter and the power spectra. At the critical point the behavior of the model is totally independent of the number of hierarchical levels. Also scaling properties are observed when the size of the system varies. The presence of noise in the communication is shown to break the transition. The analytical results are a useful guide to forecasting the main features of real networks.

Good practice for dialogue and communication as strategic principle for policing political manifestations in Europe (GODIAC):field study handbook

This handbook describes the peer review methodology that was applied at the GODIAC project fi eld studies1. The peer review evaluation method as initiated by Otto Adang in the Netherlands and further developed in a European football context (Adang & Brown, 2008) involves experienced police offi cers cooperating with researchers to perform observational fi eld studies to identify good practices and learning points for public order management. The handbook builds on the GODIAC seminars and workshops, for the fi eld study members, which took place in September 2010, January 2012 and January 2013. The handbook has been discussed in the project group and in the steering committee. It is primarily written for the GODIAC fi eld study members as background material for understanding the fi eld study process and for clarifying the different responsibilities that enable active participation in the fi eld study. The handbook has been developed during the project period and incorporates learning points and developments of the peer review method. The handbook aims at promoting the use of fi eld studies for evaluation of policing major events.

Good practice for dialogue and communication as strategic principle for policing political manifestations in Europe (GODIAC):the anthology

The volume is divided into two parts; the fi rst deals with issues related to the police, and the second addresses issues related to demonstrators and protesters. We hope that this volume will provide further insight into issues associated with policing at major events and shed light on the complexity of the organisations, motives, and strategies in play whenever protester groups are involved.

Good practice for dialogue and communication as strategic principle for policing political manifestations in Europe (GODIAC):recommendations for policing political manifestations in Europe

This report summarises the fi eld study results of the project ’Good practice for dialogue and communication as strategic principles for policing political manifestations in Europe’ (GODIAC).1 The overall idea was to integrate operative police work, research and training within the fi eld and to build international and institutional networks, ensuring and recognising the responsibilities of the organisers. The purpose of the GODIAC project was to contribute to the development of a European approach to policing political manifestations.

Anne Gangloff, Dion Chrysostome et les mythes. Hellénisme, communication et philosophie politique, París (J. Millon) 2006.

Thi book, as its author makes clear, is based on a thesis that set out initially to analyse what the myths in the works of Dio Chrysostom actually represented but as Gangloff proceeded whit her research her analysis became rather an examination of how the sophist took over and reinvented myths, adpting them to his own purposes and his own times.

Premsa gratuïta, un model de comunicació local = Free press, a local communication model

The relationship between non-institutional free press and local communication is quite particular since this type of press forms a very characteristic model of local communication, showing that advertising suffices to finance an information product addressed to a fairly well-defined readership as long as this product has a good advertising sales department and an effective distribution in its operating area. This paper discusses the present situation of the free press in Catalonia, where this phenomenon has been quite prominent. It points out the main features of this type of press and makes a review of its history, which runs from the euphoria of its early years and its expansion and consolidation, to the current crisis

Intrinsic subspace convergence in TDD MIMO communication

In numerical linear algebra, students encounter earlythe iterative power method, which finds eigenvectors of a matrixfrom an arbitrary starting point through repeated normalizationand multiplications by the matrix itself. In practice, more sophisticatedmethods are used nowadays, threatening to make the powermethod a historical and pedagogic footnote. However, in the contextof communication over a time-division duplex (TDD) multipleinputmultiple-output (MIMO) channel, the power method takes aspecial position. It can be viewed as an intrinsic part of the uplinkand downlink communication switching, enabling estimationof the eigenmodes of the channel without extra overhead. Generalizingthe method to vector subspaces, communication in thesubspaces with the best receive and transmit signal-to-noise ratio(SNR) is made possible. In exploring this intrinsic subspace convergence(ISC), we show that several published and new schemes canbe cast into a common framework where all members benefit fromthe ISC.

Simulating Communication Routes in Mediterranean Alluvial Plains

Societies exchange knowledge, ideas and merchandise throughout their territories. Topography plays a fundamental role in the trajectory of such movements whilst helping to explain the distribution of human constructions. Standard GIS functions have been employed widely to simulate communication routes between settlements, but the straight application of published least cost route models proved inadequate for Mediterranean alluvial plain areas in which seasonal floods become an important factor to acknowledge. The objective of this study is the production of a new model, using topographic and hydrologic factors as variables from which it would be possible to simulate a route, and test it against known Roman itineraries. The selected Roman stretches are Girona – Coll de Pannisars and Tarragona – Montblanc. The new model shows the need to consider each case individually but also stresses the hydrologic factor, expressed in seasonal floods, as being of prime importance in the creation and development of Roman roads in Mediterranean alluvial plains.

Short communication. Persistence of point crop yield subjective estimates

En este trabajo se investiga la persistencia de las estimaciones puntuales subjetivas de rendimientos en cultivos anua- les realizadas por un amplio grupo de agricultores. La persistencia en el tiempo es una condición necesaria para la co- herencia y la confiabilidad de las estimaciones subjetivas de variables aleatorias. Los sujetos entrevistados estimaron valores puntuales de rendimientos de cultivos anuales (rendimientos medio, mayor, mínimo y más frecuente). Se han encontrado diferencias relativas poco importantes en todas las variables, excepto en los rendimientos mínimos, donde existe una alta dispersión. Los resultados son interesantes para estimar la adecuación de las técnicas de estimación de probabilidades subjetivas para ser utilizadas en los sistemas de ayuda en la toma de decisiones en agricultura.