Discontinuous Galerkin methods for first-order hyperbolic problems

In this paper we consider discontinuous Galerkin (DG) finite element approximations of a model scalar linear hyperbolic equation. We show that in order to ensure continuous stabilization of the method it suffices to add a jump-penalty-term to the discretized equation. In particular, the method does not require upwinding in the usual sense. For a specific value of the penalty parameter we recover the classical discontinuous Galerkin method with upwind numerical flux function. More generally, using discontinuous piecewise polynomials of degree $k$, the familiar optimal $\mathcal{O}(h^{k+1/2})$ error estimate is proved for any value of the penalty parameter. As precisely the same jump -term is used for the purposes of stabilizing DG approximations of advection-diffusion operators, the discretization proposed here can simplify the construction of discontinuous Galerkin finite element approximations of advection-diffusion problems. Moreover, the use of the jump-stabilization makes the analysis simpler and more elegant

Residual-free bubbles for advection-diffusion problems: the general error analysis

We develop the general a priori error analysis of residual-free bubble finite element approximations to linear elliptic convection-dominated diffusion problems subject to homogeneous Dirichlet boundary condition. Optimal-order error bounds are derived in various norms, using piecewise polynomial finite elements of degree greater than or equal to 1

A simple preconditioner for a discontinuous Galerkin method for the Stokes problem

In this paper we construct Discontinuous Galerkin approximations of the Stokes problem where the velocity field is H(div)-conforming. This implies that the velocity solution is divergence-free in the whole domain. This property can be exploited to design a simple and effective preconditioner for the final linear system.Comment: 27 pages, 4 figure

Modeling Subgrid Viscosity for Advection--Diffusion Problems

We analyse the effect of the subgrid viscosity on a finite element discretisation, with piecewise linear elements, of a linear advection-diffusion scalar equation. We point out the importance of a proper tune-up of the viscosity coefficient, and we propose a heuristic method for obtaining reasonable values for it. The extension to more general problems is then hinted in the last section

Preoperative staging of colorectal cancer using virtual colonoscopy: correlation with surgical results

The aim of this study was to evaluate the clinical usefulness of computed tomography colonography (CTC) in the preoperative staging in patients with abdominal pain for occlusive colorectal cancer (CRC) and to compare the results of CTC with the surgical ones

Discontinuously supervised aerobic training vs. physical activity promotion in the self-management of type 2 diabetes in older Italian patients: design and methods of the 'TRIPL-A' randomized controlled trial

Physical activity (PA) has health benefits for people with type 2 diabetes (T2D). Indeed, regular PA is considered an important part of any T2D management plan, yet most patients adopt a sedentary lifestyle. Exercise referral schemes (ERS) have the potential to effectively promote physical activity among T2D patients, and their effectiveness may be enhanced when they are supported by computer-based technologies. The 'TRIPL-A' study (i.e., a TRIal to promote PhysicaL Activity among patients in the young-old age affected by T2D) aims to assess if realizing an innovative ERS, based on a strong partnership among general practitioners, specialist physicians, exercise specialists, and patients, and supported by a web-based application (WBA), can effectively lead sedentary older T2D patients to adopt an active lifestyle

On-cloud decision-support system for non-small cell lung cancer histology characterization from thorax computed tomography scans

Non-Small Cell Lung Cancer (NSCLC) accounts for about 85% of all lung cancers. Developing non-invasive techniques for NSCLC histology characterization may not only help clinicians to make targeted therapeutic treatments but also prevent subjects from undergoing lung biopsy, which is challenging and could lead to clinical implications. The motivation behind the study presented here is to develop an advanced on-cloud decisionsupport system, named LUCY, for non-small cell LUng Cancer histologY characterization directly from thorax Computed Tomography (CT) scans. This aim was pursued by selecting thorax CT scans of 182 LUng ADenocarcinoma (LUAD) and 186 LUng Squamous Cell carcinoma (LUSC) subjects from four openly accessible data collections (NSCLC-Radiomics, NSCLC-Radiogenomics, NSCLC-Radiomics-Genomics and TCGA-LUAD), in addition to the implementation and comparison of two end-to-end neural networks (the core layer of whom is a convolutional long short-term memory layer), the performance evaluation on test dataset (NSCLC-RadiomicsGenomics) from a subject-level perspective in relation to NSCLC histological subtype location and grade, and the dynamic visual interpretation of the achieved results by producing and analyzing one heatmap video for each scan. LUCY reached test Area Under the receiver operating characteristic Curve (AUC) values above 77% in all NSCLC histological subtype location and grade groups, and a best AUC value of 97% on the entire dataset reserved for testing, proving high generalizability to heterogeneous data and robustness. Thus, LUCY is a clinically-useful decision-support system able to timely, non-invasively and reliably provide visuallyunderstandable predictions on LUAD and LUSC subjects in relation to clinically-relevant information

O ENSINO DE LITERATURA PERPASSADO PELA TEORIA LITERÁRIA: ANÁLISES LITERÁRIAS E CONCEPÇÕES DE IDENTIDADE

O presente artigo tem como objetivo ressaltar a importância da inserção de teoria literária nas análises literárias no ensino de literatura. A meta da transmissão de pressupostos teóricos é possibilitar a conquista da leitura crítica pelos alunos do ensino médio sobre questões que envolvam a identidade e a hibridização cultural. Por meio de pesquisa bibliográfica, abordaremos três concepções de identidade, de acordo com os argumentos de Stuart Hall e outros estudiosos, para análise dos personagens de dois romances históricos contemporâneos brasileiros, “Viva o povo brasileiro”, de João Ubaldo Ribeiro, e “Cunhataí”, de Maria Filomena Boissou Lepecki