Towards a software defined multi-domain architecture for the internet of things

The emerging communication networks tend to aggregate heterogeneous networking infrastructures as well as data flows with very distinct requisites. This implies that the complete satisfaction of Quality of Service (QoS) metrics is very difficult to achieve, using the legacy management solutions. Alternatively, the Software Defined Networking (SDN) paradigm offers a logical centralized management of the necessary network resources for data flows, namely the ones originated in sensor devices. Therefore, this work investigates a solution that meets the QoS requirements of traffic from remote Internet of Thing (IoT) devices. To achieve this goal, we have designed a SDN-based solution that manages a network topology formed by several domains. We assume each network domain is controlled by its own SDN controller. In addition, our solution assumes that the several SDN controllers need to be orchestrated among them to maximize the management efficiency of the available end-to-end network resources. This orchestration is done via an SDN transit domain ruled by the ONOS SDN-IP application. We have emulated network topologies with IoT devices to evaluate the proposed solution in terms of its functionality, robustness against network failures, and QoS support. Analyzing the obtained results, our solution can support a cross-controller SDN domain communication. It is also capable of reacting automatically to topology failures. In addition, it can prioritize the traffic within the network infrastructure, providing to the end users strong guarantees on the desired quality for the exchange of data associated to the applications they aim to use.info:eu-repo/semantics/publishedVersio

Objective quality prediction model for lost frames in 3D video over TS

This paper proposes an objective model to predict the quality of lost frames in 3D video streams. The model is based only on header information from three different packet-layer levels: Network Abstraction Layer (NAL), Packetised Elementary Streams (PES) and Transport Stream (TS). Transmission errors leading to undecodable TS packets are assumed to result in frame loss. The proposed method estimates the size of the lost frames, which is used as a model parameter to predict their objective quality measured as the Structural Similarity Index Metric (SSIM). The results show that SSIM of missing stereoscopic frames in 3D coded video can be predicted with Root Mean Square Error (RMSE) accuracy of about 0.1 and Pearson correlation coefficient of 0.8, taking the SSIM of uncorrupted frames as reference. It is concluded that the proposed model is capable of estimating the SSIM quite accurately using only the lost frames estimated sizes.info:eu-repo/semantics/acceptedVersio

Cellular for the skies: exploiting mobile network infrastructure for low altitude air-to-ground communications

In this article we presented an overview of UASs for civil applications focusing on the communication component. We identified several available communication technologies for UAVs, their constraints, and also protocols available for implementing the remote operation of the vehicles. As an attractive solution for the A2G communication link for UAVs, we discussed the potential of mobile networks with their fully deployed infrastructures, wide radio coverage, high throughputs, reduced latencies, and large availability of radio modems. We described how a UAS can be implemented in a flexible and modular approach that allows it to rely on one or several wireless (UAVs and GCSs) and wired (GCSs) technologies. Despite the advantages of a system based on cellular and IP networks, there are problems that must be dealt with, namely, possible loss of radio coverage, presence of NAT, delay, jitter, and packet loss. Following the proposed architecture, we implemented an UAS and conducted some flight tests, which showed that the operation of the vehicles in semi-automatic or fully-automatic modes is feasible. It is expected that future enhancements for 4G networks and evolution to 5G will benefit UAV communications even further with lower latencies, higher throughput, and higher reliability.info:eu-repo/semantics/acceptedVersio

Remoção de compostos de azoto em lixiviados de aterros sanitários por biodiscos anaeróbios à escala piloto

Os lixiviados de aterros sanitarios de residuos sólidos urbanos constituem a fracção do sistema de confinamento de maior dificuldade de tratamento, devido a mutação das suas caracterfsticas com o tempo. Analiticamente caracterizam-se por elevados valores de CQO e CB05 especialmente quando novos, decrescendo acentuadamente com a idade do aterro sanitaria. Valores da CQO ate 40000 mg/L são comuns, assim como 25000 mg/L para a CB05, diminuindo para valores da ordem de grandeza de 200 mg/L. 0 conhecimento das caracteristicas, mecanismos de geração e tratabilidade dos lixiviados constituem desafios para a aplicação das melhores e mais eficazes tecnologias no seu tratamento. A realização de experiências em escala reduzida, constituem elementos de auxilio a decisão quanta a metodologia de tratamento a utilizar. Descreve-se nesta comunicação as experiências a escala piloto realizadas com urn reactor anaeróbio de biodiscos (AnRBC), apresentando-se os resultados com o objectivo de dar uma contribuição para urn melhor conhecimento dos tratamentos aplicados a lixiviados de aterros sanitarios. 0 AnRBC foi operado em continuo distinguindo-se uma fase inicial, Fase I, com uma alimentação sintetica usando citrato como fonte de carbona e com valores de carga azotada entre 0.726 e 5. 804 g NN03-/ m2d, e uma fase posterior, Fase II, em que se procedeu a simulação de uma composição de urn lixiviado jovem de urn aterro sanitaria de residuos sólidos urbanos aplicado com uma carga organica de 338.7 a 832.3 g CQO/m2 d, usando glucose e AGV, e uma carga azotada de 16.324 g N-N03-/m2.d. Os resultados evidenciaram que o fenómeno de desnitrificação ocorre favoravelmente nas condições experimentais implementadas, registando-se eficiencias de remoção de nitrato superiores a 90%, e potenciam o AnRBC como uma solução benefica a considerar na remoção de compostos de azoto de lixiviados de aterros sanitarios jovens de resíduos sólidos urbanos

Silica-Based Nanomaterials for Diabetes Mellitus Treatment

Diabetes mellitus, a chronic metabolic disease with an alarming global prevalence, is associated with several serious health threats, including cardiovascular diseases. Current diabetes treatments have several limitations and disadvantages, creating the need for new effective formulations to combat this disease and its associated complications. This motivated the development of therapeutic strategies to overcome some of these limitations, such as low therapeutic drug bioavailability or poor compliance of patients with current therapeutic methodologies. Taking advantage of silica nanoparticle characteristics such as tuneable particle and pore size, surface chemistry and biocompatibility, silica-based nanocarriers have been developed with the potential to treat diabetes and regulate blood glucose concentration. This review discusses the main topics in the field, such as oral administration of insulin, glucose-responsive devices and innovative administration routes

Morin Hydrate Encapsulation and Release from Mesoporous Silica Nanoparticles for Melanoma Therapy

Melanoma incidence, a type of skin cancer, has been increasing worldwide. There is a strong need to develop new therapeutic strategies to improve melanoma treatment. Morin is a bioflavonoid with the potential for use in the treatment of cancer, including melanoma. However, therapeutic applications of morin are restrained owing to its low aqueous solubility and limited bioavailability. This work investigates morin hydrate (MH) encapsulation in mesoporous silica nanoparticles (MSNs) to enhance morin bioavailability and consequently increase the antitumor effects in melanoma cells. Spheroidal MSNs with a mean size of 56.3 ± 6.5 nm and a specific surface area of 816 m2/g were synthesized. MH was successfully loaded (MH-MSN) using the evaporation method, with a loading capacity of 28.3% and loading efficiency of 99.1%. In vitro release studies showed that morin release from MH-MSNs was enhanced at pH 5.2, indicating increased flavonoid solubility. The in vitro cytotoxicity of MH and MH-MSNs on human A375, MNT-1 and SK-MEL-28 melanoma cell lines was investigated. Exposure to MSNs did not affect the cell viability of any of the cell lines tested, suggesting that the nanoparticles are biocompatible. The effect of MH and MH-MSNs on reducing cell viability was time- and concentration-dependent in all melanoma cell lines. The A375 and SK-MEL-28 cell lines were slightly more sensitive than MNT-1 cells in both the MH and MH-MSN treatments. Our findings suggest that MH-MSNs are a promising delivery system for the treatment of melanoma