Topological properties of P.A. random graphs with edge-step functions

In this work we investigate a preferential attachment model whose parameter is a function $f:\mathbb{N}\to[0,1]$ that drives the asymptotic proportion between the numbers of vertices and edges of the graph. We investigate topological features of the graphs, proving general bounds for the diameter and the clique number. Our results regarding the diameter are sharp when $f$ is a regularly varying function at infinity with strictly negative index of regular variation $-\gamma$. For this particular class, we prove a characterization for the diameter that depends only on $-\gamma$. More specifically, we prove that the diameter of such graphs is of order $1/\gamma$ with high probability, although its vertex set order goes to infinity polynomially. Sharp results for the diameter for a wide class of slowly varying functions are also obtained. The almost sure convergence for the properly normalized logarithm of the clique number of the graphs generated by slowly varying functions is also proved

Experimental assessment of RRM techniques in 5 GHz dense WiFi networks using REMs

“© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”The increasing acceptance of WiFi has created unprecedented levels of congestion in the unlicensed frequency bands, especially in densely populated areas. This results mainly because of the unmanaged interference and uncoordinated op- eration between WiFi access points. Radio Environment Maps (REM) have been suggested as a support for coordination strategies that optimize the overall WiFi network performance. In this context, the main objective of this experiment is to assess the benefit of a coordinated management of radio resources in dense WiFi networks at 5 GHz band, using REMs for indoor scenarios. It was shown that REMs can detect the presence of interfering links on the network or coverage holes, and a suitable coordination strategy can use this information to reconfigure Access Points (AP) channel assignment and re-establish the client connection, at a cost of diminishing the aggregate throughput of the network. The technique of AP hand-off was tested to balance the load from one AP to another. Using REMs, the Radio Resource Management (RRM) strategy could reconfigure the network to optimize the client distribution among available APs. Although the aggregate throughput is lower after load balancing, the RRM could increase the throughput of the overloaded AP.info:eu-repo/semantics/publishedVersio

Marshall University Department of Music presents Classical Sounds of Guitar and Violin

https://mds.marshall.edu/music_perf/1056/thumbnail.jp

Um ensaio de psicologia narrativa

Texto da lição integrada no concurso de provas públicas para recrutamento de um Professor Coordenador para a Escola Superior de Educação, na área científica da Psicologia Narrativa organizado nas seguintes três secções: (1) O mapa cognitivo; (2) A narrativa como meio de construção das significações pessoais. (3) Limites práticos e teóricos e explorações no domínio da criatividade

A new metaphor for learning?

O objectivo essencial deste artigo de reflexão é esboçar um conjunto de questões críticas sobre a aprendizagem e as TIC em educação. Para o efeito, apresentam-se três ideias: (1) há sempre uma teia metafórica na construção de uma teoria; (2) várias teorias sobre a aprendizagem podem ser compreendidas através de velhas metáforas, quer sejam ou não reconhecidas pelos seus defensores; (3) é necessário um ponto de vista diferente para uma compreensão mais extensa do ensino e da aprendizagem e para o fundamento da inserção das TIC na educação. The main goal of this paper is to outline some critical issues on learning. To that end, three ideas are developed: (1) the theoretical construction is based on metaphors, (2) various theories can be understood by old metaphors, whether or not are recognized by its advocates; (3) a different point of view is necessary to a deeper understanding of teaching and learning and to open a different foundation for integrating ICT in education

Mining legacy of Douro Coal Basin: remains of a system under process

A identificação do legado mineiro da Bacia Carbonífera do Douro levanta questões face aos paradigmas de reconhecimento patrimonial e da intervenção sobre as marcas de uma actividade económica estritamente ligada ao território que transforma e que hoje nos chegam. No território transformado pelo Sistema Carbonífero do Douro (SCD) o actual enquadramento patrimonial identifica “fragmentos” que não permitem a sua leitura como integrante de um sistema sociotécnico. Como alternativa, é apresentado um entendimento de como o Sistema se vai territorializando, sedimentando uma “paisagem antropogeográfica”. De um exclusivo reconhecimento das “construções resistentes” hoje existentes, propomos a identificação do conjunto de relações temporal e espacialmente transversais que, assumindo formas distintas em função do contexto integrado, foram determinando as morfologias do SCD, imputando-lhes a dimensão identitária inerente a um sistema produtivo motor de aculturação, possibilitando ler o Sistema como tal. Face à capacidade de representação dos valores que estabelecem vínculos entre o presente e o passado sobre a qual deverá incidir a condição patrimonial, identifica-se neste conjunto de relações as regras para a transformação futura do território que o SCD moldou, procurando-se veicular um entendimento prospectivo de património, então potenciador de uma requalificação territorial integrada e dotada de significado.The recognition of the mining legacy of Douro Coal Basin raises issues regarding the paradigms of heritage recognition and of intervention on the present marks of an economic activity strictly linked to the territory, so transformed by it. In the territory transformed by the Carboniferous System of Douro (SCD) the current heritage context identifies only “fragments”, which don’t allow their understanding as an integrated part of a sociotechnical system. As an alternative, it is proposed the understanding of how the SCD was being territorialized and settling an “anthropogeographic landscape”. This paper identifies temporal and spatial correlations that supported SCD territorialisation. These correlations assumed distinct forms according to the surrounding context and determined SCD morphologies, attributing to them the identity inherent to a productive system that enhanced acculturation and allowing its perception as a system. The evaluation of heritage condition and future interventions should consider values and needs that result from the links between present and past. Under this assumption, a group of intervention principles for the transformation of the SCD territory are identified. The goal is to move closer to a prospective understanding of heritage, enabling an integrated and meaningful territory requalification.Peer Reviewe

O educador contador de histórias: uma introdução

Com base na já clássica distinção bruneriana entre pensamento paradigmático e pensamento narrativo, apresenta~se a ideia de a narrativa ser um recurso simbólico para a construção de significados pessoais e colectivos. Apresenta-se um modelo de sete dimensões estruturais que uma narrativa bem construída e significativa poderá seguir tendo em vista a educação e o desenvolvimento emocional das crianças

Tolerant, broadband tunable 2 × 2 coupler circuit

We propose a circuit design for a broadband tunable 2 x 2 waveguide coupler, consisting of a two-stage Mach-Zehnder interferometer with electro-optic phase shifters in each stage. We demonstrate that such design can be configured as a tunable coupler with arbitrary coupling ratio and with a uniform response over 50-nm spectral range around 1550 nm. The design is also tolerant to fabrication variations that affect the coupling ratios of the directional couplers