Models with three Higgs doublets in the triplet representations of A(4) or S-4

We consider the quark sector of theories containing three scalar SU(2)(L) doublets in the triplet representation of A(4) (or S-4) and three generations of quarks in arbitrary A(4) (or S-4) representations. We show that for all possible choices of quark field representations and for all possible alignments of the Higgs vacuum expectation values that can constitute global minima of the scalar potential, it is not possible to obtain simultaneously nonvanishing quark masses and a nonvanishing CP-violating phase in the Cabibbo-Kobayashi-Maskawa quark mixing matrix. As a result, in this minimal form, models with three scalar fields in the triplet representation of A(4) or S-4 cannot be extended to the quark sector in a way consistent with experiment. DOI: 10.1103/PhysRevD.87.055010.

Minimal anomaly-free chiral fermion sets and gauce coupling unification

We look for minimal chiral sets of fermions beyond the standard model that are anomaly free and, simultaneously, vectorlike particles with respect to color SU(3) and electromagnetic U(1). We then study whether the addition of such particles to the standard model particle content allows for the unification of gauge couplings at a high energy scale, above 5.0 x 10(15) GeV so as to be safely consistent with proton decay bounds. The possibility to have unification at the string scale is also considered. Inspired in grand unified theories, we also search for minimal chiral fermion sets that belong to SU(5) multiplets, restricted to representations up to dimension 50. It is shown that, in various cases, it is possible to achieve gauge unification provided that some of the extra fermions decouple at relatively high intermediate scales.

A two-Higgs doublet model with remarkable CP properties

We analyze generalized CP symmetries of two-Higgs doublet models, extending them from the scalar to the fermion sector of the theory. We show that, other than the usual CP transformation, there is only one of those symmetries which does not imply massless charged fermions. That single model which accommodates a fermionic mass spectrum compatible with experimental data possesses a remarkable feature. Through a soft breaking of the symmetry it displays a new type of spontaneous CP violation, which does not occur in the scalar sector responsible for the symmetry breaking mechanism but, rather, in the fermion sector.

Basis invariant conditions for supersymmetry in the two-Higgs-doublet model

The minimal supersymmetric standard model involves a rather restrictive Higgs potential with two Higgs fields. Recently, the full set of classes of symmetries allowed in the most general two-Higgs-doublet model was identified; these classes do not include the supersymmetric limit as a particular class. Thus, a physically meaningful definition of the supersymmetric limit must involve the interaction of the Higgs sector with other sectors of the theory. Here we show how one can construct basis invariant probes of supersymmetry involving both the Higgs sector and the gaugino-Higgsino-Higgs interactions.

Controlo tolerante a falhas de um canal de rega

A presente dissertação pretende conceber e implementar um sistema de controlo tolerante a falhas, no canal experimental de rega da Universidade de Évora, utilizando um modelo implementado em MATLAB/SIMULINK®. Como forma de responder a este desafio, analisaram-se várias técnicas de diagnóstico de falhas, tendo-se optado por técnicas baseadas em redes neuronais para o desenvolvimento de um sistema de detecção e isolamento de falhas no canal de rega, sem ter em conta o tipo de sistema de controlo utilizado. As redes neuronais foram, assim, os processadores não lineares utilizados e mais aconselhados em situações onde exista uma abundância de dados do processo, porque aprendem por exemplos e são suportadas por teorias estatísticas e de optimização, focando não somente o processamento de sinais, como também expandindo os horizontes desse processamento. A ênfase dos modelos das redes neuronais está na sua dinâmica, na sua estabilidade e no seu comportamento. Portanto, o trabalho de investigação do qual resultou esta Dissertação teve como principais objectivos o desenvolvimento de modelos de redes neuronais que representassem da melhor forma a dinâmica do canal de rega, de modo a obter um sistema de detecção de falhas que faça uma comparação entre os valores obtidos nos modelos e no processo. Com esta diferença de valores, da qual resultará um resíduo, é possível desenvolver tanto o sistema de detecção como de isolamento de falhas baseados nas redes neuronais, possibilitando assim o desenvolvimento dum sistema de controlo tolerante a falhas, que engloba os módulos de detecção, de isolamento/diagnóstico e de reconfiguração do canal de rega. Em síntese, na Dissertação realizada desenvolveu-se um sistema que permite reconfigurar o processo em caso de ocorrência de falhas, melhorando significativamente o desempenho do canal de rega.

SU(5) x SU(5) unification revisited

The idea of grand unification in a minimal supersymmetric SU(5) x SU(5) framework is revisited. It is shown that the unification of gauge couplings into a unique coupling constant can be achieved at a high-energy scale compatible with proton decay constraints. This requires the addition of minimal particle content at intermediate energy scales. In particular, the introduction of the SU(2)(L) triplets belonging to the (15, 1)+((15) over bar, 1) representations, as well as of the scalar triplet Sigma(3) and octet Sigma(8) in the (24, 1) representation, turns out to be crucial for unification. The masses of these intermediate particles can vary over a wide range, and even lie in the TeV region. In contrast, the exotic vector-like fermions must be heavy enough and have masses above 10(10) GeV. We also show that, if the SU(5) x SU(5) theory is embedded into a heterotic string scenario, it is not possible to achieve gauge coupling unification with gravity at the perturbative string scale.

Indoor air quality in Portuguese archives: a snapshot on exposure levels

Indoor air quality recently entered legislation in Portugal. Several parameters must be evaluated and kept within limits in order to obtain a certification for air quality and energy consumption. Certification parameters were analyzed in two Portuguese archives in order to assess indoor air quality both for people attending or working on these premises and for maintenance of a written heritage that must be retained for future generations. Carbon monoxide (CO) and carbon dioxide (CO2), formaldehyde, and fungal counts were kept within stipulated limits. Relative humidity (RH), volatile organic compounds (VOC), particulate matter (PM10), and ozone (O3) showed values above legislated levels and justified the implementation of corrective measures. In terms of conservation, studies on the limit values are still needed, but according to the available international guidelines, some of the analyzed parameters such as PM10, O3, and RH were also above desirable values. Corrective measures were proposed to these institutions. Although this study was only of a short duration, it proved valuable in assessing potential eventual problems and constitutes the first Portuguese indoor air quality assessment taking into consideration both aspects of an archive such as human health and heritage safekeeping.

Geometric picture of generalized-CP and Higgs-family transformations in the two-Higgs-doublet model

In the two-Higgs-doublet model (THDM), generalized-CP transformations (phi(i) -> X-ij phi(*)(j) where X is unitary) and unitary Higgs-family transformations (phi(i) -> U-ij phi(j)) have recently been examined in a series of papers. In terms of gauge-invariant bilinear functions of the Higgs fields phi(i), the Higgs-family transformations and the generalized-CP transformations possess a simple geometric description. Namely, these transformations correspond in the space of scalar-field bilinears to proper and improper rotations, respectively. In this formalism, recent results relating generalized CP transformations with Higgs-family transformations have a clear geometric interpretation. We will review what is known regarding THDM symmetries, as well as derive new results concerning those symmetries, namely how they can be interpreted geometrically as applications of several CP transformations.

As relações intergeracionais e as sociedades envelhecidas : Envelhecer numa sociedade não Stop – O território multigeracional de Lisboa Oriental

A dissertação de mestrado subordinada ao tema das Relações Intergeracionais e as Sociedades Envelhecidas surgiu, no âmbito do Mestrado em Educação Social e Intervenção Comunitária, da Escola Superior de Educação de Lisboa e teve como ponto de partida saber se a participação em actividades intergeracionais promove o envelhecimento ativo de 8 mulheres com 65 e mais anos, residentes num território multigeracional de Lisboa Oriental. A abordagem concetual do envelhecimento social, do envelhecimento ativo, das relações intergeracionais e da participação conduziu o estudo, através da triangulação dos instrumentos de análise qualitativa de entrevistas de histórias de vida e de focus group. As mulheres entrevistadas têm entre 65 e 85 anos de idade cronológica, mas em média dizem sentir que têm menos 34 anos. Afirmam, ser jovens de espirito e por isso preferem ser chamadas de seniores. Manifestam que sempre foram e são, mulheres autónomas, livres, independentes, com poder de decisão, com auto-estima elevada e com qualidade de vida. Mulheres que ocupam o tempo em actividades da vida diária, em actividades de tempos livres, e voluntariado. Mulheres reivindicativas, proativas, frontais e determinadas que assumem um papel social ativo envolvendo-se socialmente em todas as actividades produtivas ou orientadas para a performance e em actividades colectivas e ou orientadas para a união, com vista alcançar objetivos comuns. Mulheres, que ganham prestígio e estatuto na comunidade por se envolverem socialmente no processo de tomadas de decisão, organização, execução e avaliação, com as gerações mais novas. São visionárias ancestrais de espirito jovem que abrem novas portas para a construção social da velhice nas sociedades neoliberais e desafiam os humanistas quando afirmam que as atividades produtivas na velhice dão sentido à própria existência. São histórias de mulheres que nos fazem acreditar que a participação social contribui espontaneamente para o diálogo entre as gerações, em todas as fases da vida. - Abstract A dissertation on the subject of Intergenerational Relationships and Societies Aged emerged within the Master of Education Social and Community Intervention, School of Education and Lisbon had as starting point whether participation promotes intergenerational activities on aging 8 active women aged 65 years and older, residing in the territory of Eastern Lisbon multigenerational. The conceptual approach of social aging, active aging, intergenerational relations and participation conducted the study through triangulation of instruments qualitative analysis of interviews and life stories focus group. The women interviewed are between 65 and 85 years of chronological age, but on average say they feel they are under 34 years old. They claim to be young in spirit and so they prefer to be called seniors. Demonstrate that have always been and are women autonomous, free, independent, decision-making, self-esteem and quality of life. Women who occupy the time in activities of daily life, in leisure activities, and volunteering. Women reivindicativas, proactive, front and determined to play an active social role by engaging in socially productive activities or any performance-oriented and collective activities and or targeted at the union in order to achieve common objectives. Women who gain prestige and status in the community by becoming involved socially in the process of decision making, organization, implementation and evaluation with the younger generations. They are young visionary spirit of ancestors that open new doors to the social construction of old age in neoliberal societies and challenge humanists say when productive activities in old age give meaning to their own existence. These are stories of women who have us believe that social participation contributes to spontaneous dialogue between generations, in all stages of life.

O desenvolvimento da leitura em função de diferentes métodos

Dissertação apresentada à Escola Superior de Educação de Lisboa no âmbito do Mestrado em Ensino Especial

Tradição em transformação: representações sociais de tradição em associações culturais

Dissertação conducente à obtenção do grau de Mestre em Educação Social e Intervenção Comunitária

Divulgação de indicadores sociais: outra dimensão para informações contabilísticas

Mestrado em Contabilidade