Transacção de componentes multimédia suportada por agentes

O objectivo do projecto descrito nesta dissertação é o desenvolvimento da interface entre as empresas e a plataforma Business-to-Business (B2B) de negociação automática de anúncios em construção. A plataforma, no seu todo, deve garantir que os intervalos da programação são preenchidos com um alinhamento de anúncios compatível com os interesses expressos e o perfil construído dos espectadores. A plataforma funciona como um mercado electrónico de negociação automática destinado a agências de publicidade (empresas produtoras) e empresas provedoras de conteúdos e serviços multimédia aos consumidores finais (empresas distribuidoras). As empresas, uma vez registadas na plataforma, passam a ser representadas por agentes que negoceiam automaticamente os itens submetidos com o comportamento especificado. Do ponto de vista da arquitectura, a plataforma consiste num sistema multiagente organizado em três camadas compostas por: (i) agentes de interface com as empresas; (ii) agentes de modelação das empresas; e (iii) agentes delegados, de duração efémera, exclusivamente criados para participar em negociações específicas de conteúdos multimédia. Cada empresa representada na plataforma possui, para além de um número indeterminado de delegados envolvidos em negociações específicas, dois agentes: (i) o agente de interface com a empresa, que expõe um conjunto de operações de interface ao exterior através de um serviço Web, localizado na primeira camada; e (ii) o agente que modela a empresa na plataforma, que expõe através de um serviço Web um conjunto de operações aos agentes das restantes camadas da plataforma, residente na camada intermédia. Este projecto focou-se no desenvolvimento da camada superior de interface da plataforma com as empresas e no enriquecimento da camada intermédia. A realização da camada superior incluiu a especificação da parte da ontologia da plataforma que dá suporte às operações de interface com o exterior, à sua exposição como serviços Web e à criação e controlo dos agentes de interface. Esta camada superior deve permitir às empresas carregar e descarregar toda informação relevante de e para a plataforma, através de uma interface gráfica ou de forma automática, e apresentar de forma gráfica e intuitiva os resultados alcançados, nomeadamente, através da apresentação da evolução das transacções. Em relação à camada intermédia, adicionou-se à ontologia da plataforma a representação do conhecimento de suporte às operações de interface com a camada superior, adoptaram-se taxonomias de classificação de espectadores, anúncios e programas, desenvolveu-se um algoritmo de emparelhamento entre os espectadores, programas e anúncios disponíveis e, por fim, procedeu-se ao armazenamento persistente dos resultados das negociações. Do ponto de vista da plataforma, testou-se o seu funcionamento numa única plataforma física e assegurou-se a segurança e privacidade da comunicação entre empresa e plataforma e entre agentes que representam uma mesma empresa.

Modelling adhesive joints with cohesive zone models: effect of the cohesive law shape of the adhesive layer

Adhesively-bonded joints are extensively used in several fields of engineering. Cohesive Zone Models (CZM) have been used for the strength prediction of adhesive joints, as an add-in to Finite Element (FE) analyses that allows simulation of damage growth, by consideration of energetic principles. A useful feature of CZM is that different shapes can be developed for the cohesive laws, depending on the nature of the material or interface to be simulated, allowing an accurate strength prediction. This work studies the influence of the CZM shape (triangular, exponential or trapezoidal) used to model a thin adhesive layer in single-lap adhesive joints, for an estimation of its influence on the strength prediction under different material conditions. By performing this study, guidelines are provided on the possibility to use a CZM shape that may not be the most suited for a particular adhesive, but that may be more straightforward to use/implement and have less convergence problems (e.g. triangular shaped CZM), thus attaining the solution faster. The overall results showed that joints bonded with ductile adhesives are highly influenced by the CZM shape, and that the trapezoidal shape fits best the experimental data. Moreover, the smaller is the overlap length (LO), the greater is the influence of the CZM shape. On the other hand, the influence of the CZM shape can be neglected when using brittle adhesives, without compromising too much the accuracy of the strength predictions.

A complex protocol layer as a linux user-space process

With the current complexity of communication protocols, implementing its layers totally in the kernel of the operating system is too cumbersome, and it does not allow use of the capabilities only available in user space processes. However, building protocols as user space processes must not impair the responsiveness of the communication. Therefore, in this paper we present a layer of a communication protocol, which, due to its complexity, was implemented in a user space process. Lower layers of the protocol are, for responsiveness issues, implemented in the kernel. This protocol was developed to support large-scale power-line communication (PLC) with timing requirements.

A smart layer for remote laboratories

Commonly, when a weblab is developed to support remote experiments in sciences and engineering courses, a particular hardware/software architecture is implemented. However, the existence of several technological solutions to implement those architectures difficults the emergence of a standard, both at hardware and software levels. While particular solutions are adopted assuming that only qualified people may implement a weblab, the control of the physical space and the power consumption are often forgotten. Since controlling these two previous aspects may increase the quality of the weblab hosting the remote experiments, this paper proposes the useof a new layer implemented by a domotic system bus with several devices (e.g. lights, power sockets, temperature sensors, and others) able to be controlled through the Internet. We also provide a brief proof-of-concept in the form of a weblab equipped with a simple domotic system usually implemented in smart houses. The added value to the remote experiment hosted at the weblab is also identified in terms of power savings and environment conditions.

Physical layer aware network architecture for the future internet

In this article, physical layer awareness in access, core, and metro networks is addressed, and a Physical Layer Aware Network Architecture Framework for the Future Internet is presented and discussed, as proposed within the framework of the European ICT Project 4WARD. Current limitations and shortcomings of the Internet architecture are driving research trends at a global scale toward a novel, secure, and flexible architecture. This Future Internet architecture must allow for the co-existence and cooperation of multiple networks on common platforms, through the virtualization of network resources. Possible solutions embrace a full range of technologies, from fiber backbones to wireless access networks. The virtualization of physical networking resources will enhance the possibility of handling different profiles, while providing the impression of mutual isolation. This abstraction strategy implies the use of well elaborated mechanisms in order to deal with channel impairments and requirements, in both wireless (access) and optical (core) environments.

The thickness of the transport layer in stratified geomorphic flows

River Flow 2010

Aplicação do multi-layer stream mapping para a gestão da eficiência de recursos e produtividade de um sistema de produção

Mestrado em Engenharia Mecânica – Especialização Gestão Industrial

Intestinal microsporidiosis in HIV-positive patients with chronic unexplained diarrhea in Rio de Janeiro, Brazil: diagnosis, clinical presentation and follow-up

After the diagnosis of two cases of microsporidial intestinal infection in 1992, in Rio de Janeiro, we have started looking for this parasite in HIV-infected patients with chronic unexplained diarrhea. We have studied 13 patients from Hospital Evandro Chagas, IOC-FIOCRUZ. Fecal specimens from these patients were examined for the presence of Cryptosporidia and Microsporidia, in addition to routine examination. Spores of Microsporidia were found in the stools of 6 (46.1%) of the 13 patients studied, with 2 histological jejunal confirmations. The Microsporidia-infected patients presented chronic diarrhea with about 6 loose to watery bowel movements a day. Five infected patients were treated with Metronidazole (1.5 g/day). They initially showed a good clinical response, but they never stopped eliminating spores. After about the 4th week of therapy, their diarrhea returned. Two patients utilized Albendazole (400 mg/day-4 weeks) with a similar initial improvement and recurrence of the diarrhea. Intestinal Microsporidiosis seems to be a marker of advanced stages of AIDS, since 5 of our 6 infected patients were dead after a 6 month period of follow-up. The present study indicates that intestinal microsporidiosis may be a burgeoning problem in HIV-infected patients with chronic diarrhea in Brazil, which deserves further investigation.

The use of cyclosporine modifies the clinical and histopathological presentation of tuberculosis after renal transplantation

Tuberculosis is one of the most frequent opportunistic infections after renal transplantation and occurred in 30 of 1264 patients transplanted between 1976 and 1996 at Hospital São Paulo - UNIFESP and Hospital Dom Silvério, Brazil. The incidence of 2.4% is five times higher than the Brazilian general population. The disease occurred between 50 days to 18 years after the transplant, and had an earlier and worse development in patients receiving azathioprine, prednisone and cyclosporine, with 35% presenting as a disseminated disease, while all patients receiving azathioprine and prednisone had exclusively pulmonary disease. Ninety percent of those patients had fever as the major initial clinical manifestation. Diagnosis was made by biopsy of the lesion (50%), positivity to M. tuberculosis in the sputum (30%) and spinal cerebral fluid analysis (7%). Duration of treatment ranged from 6 to 13 months and hepatotoxicity occurred in 3 patients. The patients who died had a significant greater number of rejection episodes and received higher doses of corticosteroid. In conclusion, the administration of cyclosporine changed the clinical and histopathological pattern of tuberculosis occurring after renal transplantation.

Cerebral Sinovenous Thrombosis in Children: Clinical Presentation and Extension, Localization and Recanalization of Thrombosis

Many important questions regarding pathophysiology and treatment of cerebral sinovenous thrombosis need clarification and may depend on further knowledge on the etiology, site, extension and recanalization of the thrombosis. We studied these variables in a cohort of children and adolescents from seven Portuguese Centers. We conclude from our results that the deep venous system and the superior longitudinal sinus are less frequently affected with thrombosis but have a greater potential for serious neurologic disease and for major sequelae. Non-recanalization, at least in the long term, is not an adverse prognostic factor. Extensive propagation of the thrombus from the initial site of origin seems to be common. The early identification of risk factors and their treatment coupled with an aggressive attitude towards diagnosis and treatment for thrombosis involving the deep venous system would be warranted.

Transformation of a Cutaneous Follicle Center Lymphoma to a Diffuse Large B-Cell Lymphoma - An Unusual Presentation

Primary cutaneous follicle center lymphoma (PCFCL) is characterized by a proliferation of follicle center cells in the skin. A definitive diagnosis is frequently delayed because of difficulties in interpretation of the histopathologic findings. It has an excellent prognosis with a 5-year survival over 95% and its risk of transformation has not been established. We describe a case report of man with a gastric diffuse large B-cell lymphoma (DLBCL) referred to our clinic because of nodules in the back that had gradually developed over a period of 10 years. A biopsy performed 3 years before was interpreted as reactive follicular hyperplasia. A new skin biopsy revealed a diffuse large B-cell lymphoma and immunoglobulin heavy chain gene rearrangements from the initial skin biopsy (PCBCL) and the DLBCL gastric biopsy were studied by polymerase chain reaction and an identical clonal rearrangement was detected which was highly suggestive of a transformation lymphoma.

Paracoccidioidomycosis in children: clinical presentation, follow-up and outcome

From February, 1981 to May, 2001, 63 children under 15 y old (ages 2 - 15 y, median = 8 y, mean ± 1 SD = 8 ± 3 y) presenting 70 episodes of Paracoccidioidomycosis were admitted. The main clinical manifestations and laboratory features observed upon admission were: lymph node enlargement (87.1%), fever (75.7%), weakness (48.6%), pallor (41.4%), hepatomegaly (40%), splenomegaly (35.7%), anemia (90%), hypergammaglobulinemia (88.5%), eosinophilia (75.5%) and hypoalbuminemia (72.5%). Moderate to severe malnutrition was detected in 35.7% of the episodes (Gomez's criterion). Radiographic and technetium studies showed bone lesions in 20 of the episodes, most of them being multiple lytic lesions, involving both long (70%) and plain bones (30%). First line treatment consisted of an association of sulfametoxazole-trimethoprin, which was used, exclusively, in 50 episodes. Follow-up of hemoglobin levels, number of eosinophils in the peripheral blood, albumin and gammaglobulin serum levels revealed significant sequential improvement one and six months after hospital admission, being quite useful to evaluate treatment effectiveness. Six patients died (9.3%) and four developed sequelae (6.3%) . In conclusion, the juvenile and disseminated forms can be observed in about 70% of the episodes of PCM occurring in children younger than 15 y old, most of them presenting with a febrile lymphoproliferative syndrome associated to anemia, eosinophilia and hypergammaglobulinemia.

Cross-Layer Admission Control to Enhance the Support of Real-Time Applications in WSN

Real-time monitoring applications may be used in a wireless sensor network (WSN) and may generate packet flows with strict quality of service requirements in terms of delay, jitter, or packet loss. When strict delays are imposed from source to destination, the packets must be delivered at the destination within an end-to-end delay (EED) hard limit in order to be considered useful. Since the WSN nodes are scarce both in processing and energy resources, it is desirable that they only transport useful data, as this contributes to enhance the overall network performance and to improve energy efficiency. In this paper, we propose a novel cross-layer admission control (CLAC) mechanism to enhance the network performance and increase energy efficiency of a WSN, by avoiding the transmission of potentially useless packets. The CLAC mechanism uses an estimation technique to preview packets EED, and decides to forward a packet only if it is expected to meet the EED deadline defined by the application, dropping it otherwise. The results obtained show that CLAC enhances the network performance by increasing the useful packet delivery ratio in high network loads and improves the energy efficiency in every network load.