Realizing the supersymmetric inverse seesaw model in the framework of R-parity violation

If, on one hand, the inverse seesaw is the paradigm of TeV scale seesaw mechanism, on the other it is a challenge to find scenarios capable of realizing it. In this work we propose a scenario, based on the framework of R-parity violation, that realizes minimally the supersymmetric inverse seesaw mechanism. In it the energy scale parameters involved in the mechanism are recognized as the vacuum expectation values of the scalars that compose the singlet superfields $\hat N^C$ and $\hat S$. We develop also the scalar sector of the model and show that the Higgs mass receives a new tree-level contribution that, when combined with the standard contribution plus loop correction, is capable of attaining $125$GeV without resort to heavy stops.Comment: Minor modification of the text. Final version to be published in PL

Bounds on the Simplest Little Higgs Model Mass Spectrum Through Z Leptonic Decay

We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width $Z \to e^+e^-$. Using the precision electroweak data we obtain a strong lower bound $f\geq 5.6$ TeV at 95% C.L. on the characteristic energy scale of the model. It results in a lower bound for the new gauge bosons $W^{\prime\pm}$ and $Z^{\prime}$ as being $M_{W^{\prime\pm}}\geq 2.6$ TeV and $M_{Z^{\prime}}\geq 3.1$ TeV, respectively. We also present the allowed values of the $k=f_1/f_2$ which is the parameter relating the two vacuum expectation values of the scalar triplets in the model, and the $\mu$ parameter of a quadratic term, involving the triplets, necessary to provide an acceptable mass range for the standard Higgs boson.Comment: New references added, 13 pages. Version to be publishe

The behaviour of GFRP reinforced concrete columns under monotonic and cyclic axial compression

PRAXIS XXI Project nº CEG 3/3.1/2572-95Retrofitting reinforced concrete columns with FRP materials is a recent but established technique based on their high strength/weight ratio and on other relative advantages, including the fact that FRP external shells prevent or mitigate environmental degradation of the concrete and consequent corrosion of the steel reinforcement. These techniques require, nevertheless, further studies and this paper presents and discusses experimental results obtained in tests of RC columns jacketed with GFRP under monotonic and cyclic axial compression, topic especially relevant when interventions on seismic zones are required. In order to evaluate the effect of the loading type on strength and ductility, 27 circular columns with 750mm height and 150 mm diameter, either of plain concrete or of RC, were tested. Among these circular columns, 11 were confined with two plies of CFRP whereas six were confined with three plies of GFRP. Comparison of results with proposed empirical models is shown.authorsversionpublishe

A SDSS for integrated management of health and education facilities at the local level : challenges and opportunities in a developing country

The objective of this paper is to discuss challenges and opportunities met during the development of a SDSS (Spatial Decision Support System) for integrated management of health and education facilities at the local level in Brazil. The goal of the proposed system is to seek for an optimal arrangement of health and education facilities in medium-sized cities, in order to reduce both facilities construction costs and user's transportation costs that ought to be produced during a time span of two to four decades. Some of the operational difficulties observed during the early implementation steps of the proposed SDSS are discussed in this paper. Apparently, they can be relevant in the practical application of similar systems. The described experience also suggests that the implementation of systems like the one proposed here can be an opportunity to drive a change in the way that local governments in developing countries deal with planning

Avaliação multicritério e SIG vectorial: uma alternativa para planeamento de transportes

Este trabalho tem por objectivo apresentar um modelo concebido para permitir a integração de métodos de avaliação multicritério em ambiente SIG vectorial. A avaliação da acessibilidade, aqui modelada, para além de ser um problema típico, complexo e quase permanente no planeamento de transportes, adequa-se bem ao modelo concebido pelo fato de conter alguns dos principais elementos que caracterizam os problemas de transportes (caso da análise de fluxos em rede). O modelo proposto, além de basear-se na medição de afastamento incluindo o efeito da distância, permite também o desenvolvimento de cenários de avaliação baseados na atitude de risco e compensação entre critérios, obtendo-se desta forma um espectro estratégico de avaliação. Por fim, um exemplo de aplicação que consiste na avaliação interna de um campus universitário em Portugal, aponta o potencial do modelo proposto para a avaliação da acessibilidade, abrindo perspectivas para sua aplicação em outros problemas de transportes.The aim of this work is to present a model built to allow the integration of multicriteria evaluation methods into a vector GIS environment. The accessibility assessment, which was explored here, in addition to be a typical, complex and almost permanent problem of transport planning, fits well to the conceived model because it contains some of the main elements that characterize transport models (such as flow network analysis). The proposed modeling approach, which is more than merely a measure of separation incorporating the effect of distance, allows the development of evaluation scenarios based on different trade-off and risk attitudes, i.e., a decision strategy spectrum. Finally, an application example, which consists in the internal evaluation of a university campus in Portugal, reveals the potential of the proposed model for evaluating accessibility, therefore opening perspectives to its application to other transport problems

The Left-Right SU(3)(L)xSU(3)(R)xU(1)(X) Model with Light, keV and Heavy Neutrinos

We construct a full left-right model for the electroweak interactions based on the $SU(3)_{L}\otimes SU(3)_{R}\otimes U(1)_{X}$ gauge symmetry. The fermion content of the model is such that anomaly cancellation restricts the number of families to be a multiple of three. One of the most important features of the model is the joint presence of three light active neutrinos, three additional neutrinos at keV mass scale, and six heavy ones with masses around\textbf{$10^{11}$} GeV. They form a well-motivated part of the spectrum in the sense they address challenging problems related to neutrino oscillation, warm dark matter, and baryogenesis through leptogenesis.Comment: 11 pages. Small corrections and typos fixed. Accepted for publication in PR

Análise fisiográfica das várzeas do Baixo Tocantins: uma contribuição ao manejo e desenvolvimento dos sistemas de uso da terra.

Análise fisiográfica e a evolução das várzeas do Baixo Tocantins; Fisiologia fluvial; Adequação e limitações ambientais impostas aos subsistemas.bitstream/item/63563/1/Oriental-Doc149.PD