XTC+: descripción y análisis de un mecanismo de control de topología para los MANET

The Objective of topology control mechanisms (TCM) is to modify the natural network topology toward a determined objective. In MANETs the objective is to minimize power consumption and/or interference. In general topology control is achieved through deliberate changes in transmission power (and possibly other parameters such as antenna direction and channel selection) that directly affect the local connectivity of a node, and consequently affect the whole topology of the network. By focusing on the stage in which information is collected in an existing topology control algorithm called XTC, this paper shows the possibility of extending the network performance optimization present in this algorithm. It is then an addition to an already existing optimization concept.El objetivo de los mecanismos de control de topología (TCM) es modificar la topología de la red natural hacia un objetivo determinado. En los MANET el objetivo es minimizar el consumo de energía y/o de interferencia. En la topología general el control se alcanza mediante cambios deliberados en la potencia de transmisión (y posiblemente en otros parámetros como la dirección de la antena y la selección de canal) que afectan directamente la conectividad local de un nodo y en consecuencia, afectan toda la topología de la red. Este artículo muestra la posibilidad de prolongar la optimización del desempeño de la red presente en este algoritmo, mediante el enfoque en la etapa en que la información es recopilada en un algoritmo de control de topología existente llamado XTC. Es entonces, un complemento a un concepto de optimización ya existente

Monitoring of bioelectrical and biomechanical signals in Taekwondo training: first insights

Taekwondo is an Olympic combat sport that has gained much popularity in the last years. Portugal is not an exception to the substantial growth of this martial art. Currently there are about 4500 practitioners of this art affiliated in the national federation. Several have already produced excellent results not only in national but also in international competitions, recognized by the International Olympic Com-mittee of Portugal, Taekwondo European Union and the World Taekwondo Feder-ation (WTF). This work is a joint project between the University of Minho, Sporting Club de Braga Taekwondo section and the National Technical Team of the Portu-guese Federation of Taekwondo. It is aimed at developing a system to analyse, mon-itor and quantify the athlete performance in real time. The developed system should be able to help the athlete improve his/her technique and performance by monitoring his/her heart rate, analyzing and identifying the technical movements in the training by comparing the various movements performed, as well as quantifying variables related to the athlete’s performance. Visual cues for the heart rate and performance are indicated by LEDs. With this system, we propose a contribution to innovation and development in Taekwondo training.This work is financed by FEDER funds through the Competitivity Factors Op-erational Program - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007136. Pedro Cunha thanks FCT for PhD scholarship SFRH/BD/121994/2016. Special thanks to Coach Joaquim Peixoto, as well as Sport Club de Braga Taekwondo section and to the national team, for allowing us to use their training site, as well as seeing/participating in training to test the developed system, and in general, for all the cooperation provided.info:eu-repo/semantics/acceptedVersio

Low-redshift estimates of the absolute scale of baryon acoustic oscillations

Measurements of the characteristic length scale $r_s$ of the baryon acoustic oscillations (BAO) provide a robust determination of the distance-redshift relation. Currently, the best (sub-per cent) estimate of $r_s$ at the drag epoch is provided by Cosmic Microwave Background (CMB) observations assuming the validity of the standard $\Lambda$CDM model at $z \sim 1000$. Therefore, inferring $r_s$ from low-$z$ observations in a model-independent way and comparing its value with CMB estimates provides a consistency test of the standard cosmology and its assumptions at high-$z$. In this paper, we address this question and estimate the absolute BAO scale combining angular BAO measurements and type Ia Supernovae data. Our analysis uses two different methods to connect these data sets and finds a good agreement between the low-$z$ estimates of $r_{s}$ with the CMB sound horizon at drag epoch, regardless of the value of the Hubble constant $H_0$ considered. These results highlight the robustness of the standard cosmology at the same time that they also reinforce the need for more precise cosmological observations at low-$z$.Comment: 8 pages, 4 tables, and 3 figure

Problemas ambientais desencadeados pelo plano nacional de agroenergia: o caso de Itapuranga, Goiás.

O artigo analisa as contradições entre os discursos oficias que legitimam a política nacional agroenergética e os problemas ambientais desencadeados pela expansão da monocultura canavieira em territórios de agricultura familiar. O estudo de caso foi realizado no município goiano de Itapuranga, combinando pesquisa documental, bibliográfica e entrevistas. Conclui-se que a política agroenergética agravou os problemas ambientais em Itapuranga e provocou alterações nas relações sociedade e natureza

Model-checking temporal properties of real-time HTL programs

This paper describes a tool-supported method for the formal verification of timed properties of HTL programs, supported by the automated translation tool HTL2XTA, which extracts from a HTL program (i) an Uppaal model and (ii) a set of properties that state the compliance of the model with certain automatically inferred temporal constraints. These can be manually extended with other temporal properties provided by the user. The paper introduces the details of the proposed mechanisms as well as the results of our experimental validation.Fundação para a Ciência e a Tecnologia (FCT) - Projets Rescue (PTDC/EIA/65862/2006), FAVAS (PTDC/EIA-CCO/105034/2008), LIACC-UP Programa de Financiamento Plurianua

Verificação automatizada de sistemas de tempo real criticos

A miniaturização das componentes electrónicas permite que os sistemas computacionais tenham uma proliferação acelerada. Estes sistemas estão integrados nos mais diversos meios, por exemplo, no cartão do cidadão, nos telemóveis, nos automóveis, nos aviões, entre outros. Novas exigências surgem com a evolução destes sistemas computacionais. De facto,acapacidadedeprocessamento,porsisó,jánãoésuficienteparaopreenchimento de todos os requisitos industriais. Nos sistemas críticos a segurança e a fiabilidade são os aspectos fundamentais. Apesar de ser importante, não basta reunir condições técnicas para executar um dado conjunto de tarefas num sistema, é preciso que o sistema(como um todo) execute correctamente essas tarefas(cap. 2)

Avaliação do risco de misturas de pesticidas no Aproveitamento Hidroagrícola da Lezíria Grande de Vila Franca de Xira

Mestrado em Engenharia Agronómica. Universidade de Lisboa, Instituto Superior de AgronomiaA utilização de pesticidas constitui um meio importante para melhorar a produção agrícola. No entanto, pode causar efeitos secundários nos ecossistemas aquáticos. De forma a alcançar um Bom estado químico e ecológico das massas de água europeias, foram abordados os novos desafios da avaliação de risco. Foram aplicadas abordagens com base ecológica e específica a uma importante área agrícola de Portugal, o Aproveitamento Hidroagrícola da Lezíria Grande de Vila Franca de Xira (AHLGVFX). Num total de 12 amostras de águas de superfície analisadas, foram detetados 12 compostos de pesticidas, na sua maioria herbicidas. Apesar de não constituírem risco individual para os organismos aquáticos, as misturas de pesticidas encontradas, em três amostras recolhidas num ponto de adução do AHLGVFX, revelaram risco para o ecossistema aquático, através do cálculo de quocientes de risco com base no modelo adição da concentração, como primeira etapa da avaliação do risco de misturas de pesticidas. Os produtores primários, representados pelas algas, foram o grupo taxonómico mais sensível a estas misturas, contribuindo o herbicida oxadiazão com pelo menos 49% da toxicidade da mistura. A pressão tóxica, calculada através da fração de espécies potencialmente afetada pelas misturas de pesticidas e dos modelos de previsão da toxicidade das misturas, foi inferior a 0,18%, ou seja, redução na biodiversidade pouco significativa. Este estudo pretende contribuir para a redução dos riscos de pesticidas em águas doces, através do estabelecimento de programas de medidas de mitigação para um número limitado de pesticidas com a maior contribuição para a toxicidade total da mistura.One of the most important ways of improving agricultural production is the use of plant protection products. As this type of pesticides is used within the catchment area of freshwaters there is a potential for side-effects to occur in aquatic ecosystems. New challenges for risk assessment were addressed to achieve good chemical and ecological status in European water bodies. Site-specific and ecologically-based approaches were developed and applied to an important agricultural area of Portugal, the Lezíria Grande de Vila Franca de Xira hydro-agricultural operation. In a total of 12 analysed surface water samples, 12 pesticide compounds were detected, mostly herbicides. Although they do not pose an individual risk to aquatic organisms, the pesticide mixtures found in three samples of an important supply point of the Lezíria Grande de Vila Franca de Xira hydro-agricultural operation, revealed risk to the aquatic ecosystem, by employing risk quotients based on concentration addition as a “screening level” risk assessment of pesticide mixtures. Primary producers, represented by algae, were the taxonomic group most sensitive to these mixtures, with the herbicide oxadiazon contributing at least with 49% of the mixture toxicity. The toxic pressure, calculated through potentially affected fraction by the pesticide mixtures and models for predicting mixture toxicty, was lower than 0.18%, i.e., with a negligible reduction in biodiversity. This study aims to contribute for reducing the risks of pesticides in freshwaters, by deriving appropriate programmes of mitigation measures to a limited number of pesticides with the highest contribution to the total mixture toxicity.N/

As contradições presentes no discurso do atual Programa Nacional de Agroenergia

O Estado retomou as políticas agroenergéticas lançando, em 2005, o Programa Nacional de Agroenergia, este programa é margeado pelo ideário do “desenvolvimento sustentável”. Esse enfoque muitas vezes funciona como uma ideologia, ou seja uma arma para o exercício do poder do Estado. Sendo assim, o objetivo deste estudo é analisar a origem do poder simbólico do Estado e entender como esse poder se materializa no atual programa agroenergético, buscando desvendar os interesses do Estado que se camuflam atrás das propostas que disseminam o desenvolvimento sustentável — entendido como a busca genuína pelo desenvolvimento aliada aos benefícios socioambientais. As contradições presentes nos discursos oficiais do programa são analisadas com base na teoria do poder simbólico do Estado, proposta por Bourdieu (1990, 1996, 1998). Trata-se de um estudo de caráter comparativo com enfoque dentro de uma abordagem qualitativa baseada numa pesquisa bibliográfica e documental. Como resultado contatou-se que o Estado comumente utiliza-se de planos e programas para “produzir os problemas sociais”, ao mesmo tempo, que impõem as soluções. Porém, estas soluções nem sempre são as mais apropriadas para o conjunto da sociedade como um todo, porque busca atender determinados interesses específicos, caracterizando assim a própria expressão da violência simbólica exercida pelo Estado.---------------------------------------------The State has taken over the policies of agroenergy launching, in 2005, the National Programme of Agroenergy, this program is based on the ideas of "sustainable development". This approach often works as an ideology, that is a weapon for the exercise of state power. Therefore, the objective of this study is to analyze the origin of the symbolic power of the state and understand how that power is materialized in the current program of agroenergy, seeking unveil the interests of the state which has camouflaged behind proposals that spread sustainable development - understood as the search genuine development by allied to social benefits. Contradictions present in official speeches of the program are analyzed based on the theory of symbolic power of the State, proposed by Bourdieu (1990, 1996, 1998). It is a comparative study of character with focus within a qualitative approach based on a literature search and documentary. As a result contacted that the state commonly uses up plans and programs to "produce social problems" while imposing solutions. But these solutions are not always the most appropriate for the whole society as a whole, because quest meet certain specific interests, thus characterizing the very expression of symbolic violence exercised by the State.programa agroenergético, poder do Estado, discurso, agroenergy program, the state power, speeches, Resource /Energy Economics and Policy,