Statistical Communication Theory

Contains research objectives and reports on five research projects.National Science Foundation (Grant GP-2495)National Institutes of Health (Grant MH-04737-04)National Aeronautics and Space Administration (Grant NsG-496

The human otitis media with effusion: a numerical-based study

Otitis media is a group of inflammatory diseases of the middle ear. Acute otitis media and otitis media with effusion (OME) are its two main types of manifestation. Otitis media is common in children and can result in structural alterations in the middle ear which will lead to hearing losses. This work studies the effects of an OME on the sound transmission from the external auditory meatus to the inner ear. The finite element method was applied on the present biomechanical study. The numerical model used in this work was built based on the geometrical information obtained from The visible ear project. The present work explains the mechanisms by which the presence of fluid in the middle ear affects hearing by calculating the magnitude, phase and reduction of the normalized umbo velocity and also the magnitude and phase of the normalized stapes velocity. A sound pressure level of 90 dB SPL was applied at the tympanic membrane. The harmonic analysis was performed with the auditory frequency varying from 100 Hz to 10 kHz. A decrease in the response of the normalized umbo and stapes velocity as the tympanic cavity was filled with fluid was obtained. The decrease was more accentuated at the umbo.info:eu-repo/semantics/publishedVersio

Statistical Communication Theory

Contains reports on six research projects.National Science Foundation (Grant GP-2495)National Institutes of Health (Grant MH-04737-04)National Aeronautics and Space Administration (Grant NsG-496

Novel effects of strains in graphene and other two dimensional materials

The analysis of the electronic properties of strained or lattice deformed graphene combines ideas from classical condensed matter physics, soft matter, and geometrical aspects of quantum field theory (QFT) in curved spaces. Recent theoretical and experimental work shows the influence of strains in many properties of graphene not considered before, such as electronic transport, spin-orbit coupling, the formation of Moir\'e patterns, optics, ... There is also significant evidence of anharmonic effects, which can modify the structural properties of graphene. These phenomena are not restricted to graphene, and they are being intensively studied in other two dimensional materials, such as the metallic dichalcogenides. We review here recent developments related to the role of strains in the structural and electronic properties of graphene and other two dimensional compounds.Comment: 75 pages, 15 figures, review articl

Twisted bilayer graphene: low-energy physics, electronic and optical properties

Van der Waals (vdW) heterostructures ---formed by stacking or growing two-dimensional (2D) crystals on top of each other--- have emerged as a new promising route to tailor and engineer the properties of 2D materials. Twisted bilayer graphene (tBLG), a simple vdW structure where the interference between two misaligned graphene lattices leads to the formation of a moir\'e pattern, is a test bed to study the effects of the interaction and misalignment between layers, key players for determining the electronic properties of these stackings. In this chapter, we present in a pedagogical way the general theory used to describe lattice mismatched and misaligned vdW structures. We apply it to the study of tBLG in the limit of small rotations and see how the coupling between the two layers leads both to an angle dependent renormalization of graphene's Fermi velocity and appearance of low-energy van Hove singularities. The optical response of this system is then addressed by computing the optical conductivity and the dispersion relation of tBLG surface plasmon-polaritons

Pela construção de um repositório científico (temático) geológico

e-Terra - Revista Electrónica de Ciências da Terra ISSN 1645-0388, Volume 15 – nº 10 2010É apresentado o panorama actual, nacional e internacional, sobre o Acesso Livre ao conhecimento científico através da Web. São apresentadas estatísticas que demonstram os benefícios e a utilidade desta nova forma de divulgação do conhecimento, não apenas pelo incremento das citações, mas também pela formação dos jovens investigadores e, mesmo do ponto de vista ético. São também apresentadas estatísticas sobre as publicações periódicas de Geologia em Portugal, sobre as quais se conclui também pela necessidade da constituição de um repositório bibliográfico digital

The relationship between consumer ethnocentrism, cosmopolitanism and product country image among younger generation consumers: the moderating role of country development status

Although the differences between developed and developing countries have been extensively studied in the context of globalization strategies, few studies have so far been conducted on the relationship between country development status and the possession by countries of a favorable (or unfavorable) product country image (PCI). Moreover, the results of such studies to date have been inconclusive. The purpose of this paper is to investigate the moderating role of country developmental status on PCI coupled with two antecedents of PCI, namely consumer ethnocentrism and cosmopolitanism. The paper also distinguishes between the PCI of the home and foreign country images of respondents. We test a new model that incorporates these constructs with a sample of 2655 younger generation consumers. The results show that country development status moderates some relationships but does not moderate others. These findings have significant implications for international companies from both developed and developing countries when developing global strategy

Interpretable Subgroup Discovery in Treatment Effect Estimation with Application to Opioid Prescribing Guidelines

The dearth of prescribing guidelines for physicians is one key driver of the current opioid epidemic in the United States. In this work, we analyze medical and pharmaceutical claims data to draw insights on characteristics of patients who are more prone to adverse outcomes after an initial synthetic opioid prescription. Toward this end, we propose a generative model that allows discovery from observational data of subgroups that demonstrate an enhanced or diminished causal effect due to treatment. Our approach models these sub-populations as a mixture distribution, using sparsity to enhance interpretability, while jointly learning nonlinear predictors of the potential outcomes to better adjust for confounding. The approach leads to human-interpretable insights on discovered subgroups, improving the practical utility for decision suppor

Indicadores de digestibilidade de dietas para ovinos contendo feno de ponta de cana-de-açúcar hidrolisado.

Made available in DSpace on 2017-12-18T23:24:49Z (GMT). No. of bitstreams: 1 RBSPA2017V18N1FENODEPONTADECANA.pdf: 190963 bytes, checksum: 9b647ac7ed3ea86ec0ade23af14eb5e5 (MD5) Previous issue date: 2017-12-18bitstream/item/169216/1/RBSPA-2017-V18-N1-FENO-DE-PONTA-DE-CANA.pd

Coinductive subtyping for abstract compilation of object-oriented languages into Horn formulas

In recent work we have shown how it is possible to define very precise type systems for object-oriented languages by abstractly compiling a program into a Horn formula f. Then type inference amounts to resolving a certain goal w.r.t. the coinductive (that is, the greatest) Herbrand model of f. Type systems defined in this way are idealized, since in the most interesting instantiations both the terms of the coinductive Herbrand universe and goal derivations cannot be finitely represented. However, sound and quite expressive approximations can be implemented by considering only regular terms and derivations. In doing so, it is essential to introduce a proper subtyping relation formalizing the notion of approximation between types. In this paper we study a subtyping relation on coinductive terms built on union and object type constructors. We define an interpretation of types as set of values induced by a quite intuitive relation of membership of values to types, and prove that the definition of subtyping is sound w.r.t. subset inclusion between type interpretations. The proof of soundness has allowed us to simplify the notion of contractive derivation and to discover that the previously given definition of subtyping did not cover all possible representations of the empty type