8,497 research outputs found

    A modular web-based software solution for mobile networks planning, operation and optimization

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    Mobile networks management is increasingly critical due to heavy communications usage by customers and complex due to the multiple technologies and systems deployed. Thus, Mobile Network Operators (MNOs) are constantly looking for better software solutions and tools to help them increase network performance and manage their networks more efficiently. In this paper, we present a modular web-based software solution to tackle problems related to mobile network planning, operation and optimization. The solution is focused on a set of functional requirements carefully chosen to support the network life cycle management, from planning to Operation and Maintenance (OAM) and optimisation stages. Based on a 3-tier modular architecture and implemented using only open-source software, the solution handles multiple data sources (e.g., Drive Test (DT) and Performance Management (PM)) and multiple Radio Access Network (RAN) technologies. MNOs can explore all available data through a flexible and user-friendly web interface, that also includes map-based visualization of the network. Moreover, the solution incorporates a set of recently developed and validated RAN algorithms, supporting tasks of network diagnosis, optimization, and planning. Also, with the purpose of optimizing the network, MNOs can investigate network simulations, using the RAN algorithms, of how the network will behave under certain conditions, and visualize the outcome of those simulations.info:eu-repo/semantics/publishedVersio

    Overview of machine learning methods for Android malware identification

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    Mobile malware is growing and affecting more and more mobile users around the world. Malicious developers and organisations are disguising their malware payloads on apparently benign applications and pushing them to large app stores, such as Google Play Store, and from there to final users. App stores are currently losing the battle against malicious applications proliferation and existing malware. Detection methods based on signatures, such as those of an antivirus, are limited, new approaches based on machine learning start to be explored to surpass the limitations of traditional mobile malware detection methods, analysing not only static characteristics of the app but also its behaviour. This paper contains an overview of the existing machine learning mobile malware detection approaches based on static, dynamic and hybrid analysis, presenting the advantages and limitations of each, and a comparison between the reviewed methods.info:eu-repo/semantics/acceptedVersio

    Physico-chemical surface characterization of a bacterial population isolated from a milking machine

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    The hydrophobicity of 26 species of bacteria representative of the main genera isolated from a rubber short milk tube, which is a constituent of a cluster from a milking machine, was determined. The materials forming the cluster namely rubber, stainless steel (SS) 316, stainless steel (SS) 304, glass and polymethylmethacrylate (PMMA) were also assayed in terms of hydrophobicity. In relation with the hydrophobicity of bacteria, all the strains of Lactobacillus lactis lactis as well as of Enterococcus faecalis are hydrophobic. Concerning Pseudomonas aeruginosa and Staphylococcus sciuri, some are hydrophobic and others are hydrophilic. All the materials are hydrophobic, being rubber, SS 316 and SS 304 the most hydrophobic surfaces while glass is the less hydrophobic. The free energy of adhesion between the bacteria and the materials in aqueous medium was calculated and used to predict which material of the cluster has a higher ability for biofilm formation and by this way contribute for milk contamination due to the release of bacteria from the deposit. For all the situations studied, adhesion is thermodynamically favourable to SS 316, SS 304 and rubber and less favourable to PMMA and glass.Ministério da Agricultura, do Desenvolvimento Rural e das Pescas (INIAP) - Project AGRO 205

    Técnicas de Análise Espacial Aplicadas à Caracterização da População Idosa para Planear Cuidados de Enfermagem

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    O estudo aponta uma metodologia para caracterizar factores geodemográficos condicionantes da acessibilidade geográfica a cuidados de enfermagem, numa das regiões mais envelhecidas de Portugal, a partir do uso de Sistemas de Informação Geográfica. Analisam-se dados provenientes dos censos de população relativos aos idosos. Métodos: Utilizam-se técnicas de estatística espacial, para além das técnicas de estatística clássica. Estuda-se a autocorrelação espacial dos valores de alguns índices demográficos, caracterizando estatisticamente a existência de aglomerados na zona de estudo, recorrendo ao Índice Global de Moran. Igualmente caracteriza-se a concentração de valores elevados e de valores baixos para cada um dos índices, recorrendo ao cálculo da estatística GI*. Resultados: Identificam-se as regiões de maior envelhecimento, aquelas onde se perspectiva a maior utilização de recursos de Enfermagem por parte dos idosos. Conclusões: O estudo faz apelo à necessária gestão programática dos recursos materiais e humanos de enfermagem, perspectivando a minimização dos efeitos que a situação geodemográfica heterogénea condiciona

    Energy-lowering and constant-energy spin flips: Emergence of the percolating cluster in the kinetic Ising model

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    After a sudden quench from the disordered high-temperature T0→∞ phase to a final temperature well below the critical point TF≪Tc, the nonconserved order parameter dynamics of the two-dimensional ferromagnetic Ising model on a square lattice initially approaches the critical percolation state before entering the coarsening regime. This approach involves two timescales associated with the first appearance (at time tp1>0) and stabilization (at time tp>tp1) of a giant percolation cluster, as previously reported. However, the microscopic mechanisms that control such timescales are not yet fully understood. In this paper, to study their role on each time regime after the quench (TF=0), we distinguish between spin flips that decrease the total energy of the system from those that keep it constant, the latter being parametrized by the probability p. We show that observables such as the cluster size heterogeneity H(t,p) and the typical domain size ℓ(t,p) have no dependence on p in the first time regime up to tp1. Furthermore, when energy-decreasing flips are forbidden while allowing constant-energy flips, the kinetics is essentially frozen after the quench and there is no percolation event whatsoever. Taken together, these results indicate that the emergence of the first percolating cluster at tp1 is completely driven by energy decreasing flips. However, the time for stabilizing a percolating cluster is controlled by the acceptance probability of constant-energy flips: tp(p)∼p−1 for p≪1 (at p=0, the dynamics gets stuck in a metastable state). These flips are also the relevant ones in the later coarsening regime where dynamical scaling takes place. Because the phenomenology on the approach to the percolation point seems to be shared by many 2D systems with a nonconserved order parameter dynamics (and certain cases of conserved ones as well), our results may suggest a simple and effective way to set, through the dynamics itself, tp1 and tp in such systems

    Monitoring cell detachment by surfactants in a parallel plate flow chamber

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    The efficacy of the surfactants SDS and CTAB in detaching P. fluorescens from glass surface was evaluated in a parallel plate flow chamber. This device enables “in situ” determinations of cells detachment following the application of surfactants under well controlled hydrodynamic conditions. The results showed that SDS was able to remove almost all adhering bacteria in a short period of time, whereas CTAB did not promote much cell desorption. On the contrary, this surfactant increased the adhesion strength between cells and glass. Both surfactants promoted different alterations of cell surface properties, which explains their dissimilar effectiveness as cleansing agents.programme SAPIEN

    Towards e-cities. An Atlas to enhance the public realm through interactive urban cyber-physical devices

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    Cyber-physical devices are the backbone of a postdigital society in which the virtual and real spaces are seamlessly integrated by ubiquitous computing and networking. The incorporation of such devices in public space is a central subject of a strategic Research Project that gathers a multidisciplinary team from architecture, product design, polymer science and ICT R&D units. This paper frames the key roles of public space and ICTs for UN Sustainable Development Goals and sustainable smart cities. It also reports the architecture R&D unit review on the relations between public space, community, environment and digital interfaces. This review was materialized in an Atlas that collects, classifies and relates a corpus of heterogeneous urban cyber-physical projects case studies. We expand on three main framing concepts (Digital Twin, Interface, Awareness) and identify trends on the devices’ design and deployment strategies to counteract digitally hostile environments and early obsolescence. We also suggest the rising of new types of urban devices aiming at expanding the liveliness of urban places, the knowledge of urban life and the users’ environmental consciousness. The lessons learned from the Atlas fed the design guidelines for a developing demonstrator of a new breed of environmentally sensible interactive urban devices

    Avanços e sucessos da produção integrada de uva no vale do São Francisco.

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    A fruticultura no pólo agrícola Petrolina-PE/Juazeiro-BA, situado na região do Submédio do Vale do São Francisco, tem se caracterizado por apresentar uma rápida expansão da área cultivada, um elevado crescimento da produção e um significativo desenvolvimento do setor exportador de frutas, condicionando a região a vislumbrar uma perspectiva concreta de promover uma grande melhoria sócio-econômica. Entre as fruteiras cultivadas neste importante pólo de irrigação, com potencial para inserção no mercado externo, destaca-se a uva de mesa, responsável por 99% das exportações brasileiras de uvas finas de mesa, cuja área plantada é de aproximadamente, 10.890 ha e produção de 81.595 kg (VALEXPORT, 2009). O objetivo do trabalho foi dar continuidade às ações implementadas da Produção Integrada de Uvas Finas de Mesa e implantar este sistema em novas áreas, tendo como área piloto o Submédio do Vale do São Francisco, de acordo com as Normas Técnicas Específicas para a PI-Uva, estabelecidas pela Instrução Normativa nº 20, do MAPA
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