2,976 research outputs found

    Multi-Stage Resource Allocation in Hybrid 25G-EPON and LTE-Advanced Pro FiWi Networks for 5G Systems

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    The 5G vision is not restricted solely to the wireless domain and its challenging requirements cannot be fulfilled with- out the efficient integration of cutting-edge technologies in all portions of the telecommunications infrastructure. The promoted architectures for next generation telecommunications systems involve high capacity network domains, which operate flexibly and seamlessly to offer full Quality of Experience to all types of subscribers. The proliferation of highly demanding multimedia services and the advanced features of modern communication devices necessitate the development of end-to-end schemes which can efficiently distribute large amount of network resources anywhere and whenever needed. The paper introduces a new resource allocation scheme for cutting-edge Fiber-Wireless networks is introduced that can be applied in the fronthaul portion of 5G-enabled architectures. The adopted technologies are the forthcoming 25G-EPON for the optical domain and the 5G-ready LTE-Advanced Pro for the wireless domain. The proposed scheme performs allocation decisions based on the outcome of an adjustable multi- stage optimization problem. The optimization factors are directly related to the major considerations in bandwidth distribution, namely priority-based traffic differentiation, power awareness, and fairness provision. The conducted evaluations prove that this approach is able to ensure high efficiency in network operations

    Application-Aware Network Traffic Management in MEC-Integrated Industrial Environments

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    The industrial Internet of things (IIoT) has radically modified industrial environments, not only enabling novel industrial applications but also significantly increasing the amount of generated network traffic. Nowadays, a major concern is to support network-intensive industrial applications while ensuring the prompt and reliable delivery of mission-critical traffic flows concurrently traversing the industrial network. To this end, we propose application-aware network traffic management. The goal is to satisfy the requirements of industrial applications through a form of traffic management, the decision making of which is also based on what is carried within packet payloads (application data) in an efficient and flexible way. Our proposed solution targets multi-access edge computing (MEC)-integrated industrial environments, where on-premises and off-premises edge computing resources are used in a coordinated way, as it is expected to be in future Internet scenarios. The technical pillars of our solution are edge-powered in-network processing (eINP) and software-defined networking (SDN). The concept of eINP differs from INP because the latter is directly performed on network devices (NDs), whereas the former is performed on edge nodes connected via high-speed links to NDs. The rationale of eINP is to provide the network with additional capabilities for packet payload inspection and processing through edge computing, either on-premises or in the MEC-enabled cellular network. The reported in-the-field experimental results show the proposal feasibility and its primary tradeoffs in terms of performance and confidentiality

    Interactions of hadrons in the CALICE SiW ECAL prototype

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    This article presents results of test beams obtained for pions with energies between 2 and 10 GeV which interact in the volume of the highly granular CALICE Silicon-Tungsten electromagnetic calorimeter prototype (SiW ECAL). An algorithm optimised to ïŹnd interactions in the SiW ECAL at small hadron energies is developed. This allows identifying the interaction point in the calorimeter at an efficiency between 62% and 83% depending on the energy of the primary particle. The unprecedented granularity of the SiW ECAL allows for the distinction between different interaction types. This in turn permits more detailed examinations of hadronic models than was possible with traditional calorimeters. So far, it is possible to disentangle minimum ionising particle (MIP) events, elastic π-nucleus scattering and spallation reactions which lead to the start of a internuclear cascade or which result in a small number of highly ionising particles. Various observables are compared with predictions from hadronic physics lists as contained in the simulation toolkit geant4

    A Framework for QoS- Enabled Semantic Routing in Industrial Networks: Overall Architecture and Primary Protocols

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    The manufacturing sector represents a notable use case of the Industry 4.0 revolution, heavily stressing the capability of plants to ensure the desired QoS. Currently, manufacturing plants are characterized by an increasing amount of non-mission-critical traffic, in addition to traditional mission-critical safety-related traffic, which is negligible in comparison. Since computing and networking capabilities are no longer as abundant as in the past, there is the need to properly manage available resources. To ensure challenging QoS requirements, we propose a novel protocol suite specifically designed for our QoS-enabled semantic routing framework. Such a framework adopts an architecture that fits the characteristics of modern manufacturing environments and exploits an overlay networking solution providing a semantic routing substrate that operates both at the application and network layers

    Noise reduction and spatial resolution in CT imaging with the ASIR iterative reconstruction algorithm at different doses and contrasts – a phantom study

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    Aims and objectives The aim of this study was to quantitatively assess noise reduction and spatial resolution in computed tomography (CT) imaging with the ASIR (Adaptive Statistical Iterative Reconstruction, GE Healthcare) reconstruction algorithm at different kVp, mAs and contrasts. Methods and materials Acquisitions of the Catphan-504 phantom were performed on a PET/CT scanner (Discovery-710, GE Healthcare). CT images were reconstructed using both filtered back projection (FBP) and ASIR with different percentages of reconstruction (20%, 40%, 60%, 80%, 100%). The image noise was estimated for different values of scanning parameters (i.e. tube-load, kilovoltage, pitch, slice thickness). Then, 3D/2D/1D noise power spectrum was estimated. Also, spatial resolution was assessed by obtaining the modulation transfer function (MTF) for a wide range of scanning parameters values and different contrast objects by the circular Edge Spread Function method (using CTP404 modulus) and the Point Spread Function method (using CTP528 modulus). . Results Image noise decreased (up to 50% as compared to FBP) with increasing the percentage of ASIR reconstruction (behaviour more relevant for higher spatial frequencies). Only for low tube load (<56 mAs) and low contrast objects (polistirene with respect to PMMA) acquisitions, MTF analysis showed that ASIR-reconstructed images were characterized by an appreciable reduction in spatial resolution, when compared to FBP-reconstructed images. Conclusion When compared to FBP, ASIR allows a relevant noise reduction without appreciably affecting image quality, except for very low dose and contrast acquisitions

    Optimal storage of a single photon by a single intra-cavity atom

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    We theoretically analyse the efficiency of a quantum memory for single photons. The photons propagate along a transmission line and impinge on one of the mirrors of a high-finesse cavity. The quantum memory is constituted by a single atom within the optical resonator. Photon storage is realised by the controlled transfer of the photonic excitation into a metastable state of the atom and occurs via a Raman transition with a suitably tailored laser pulse, which drives the atom. Our study is supported by numerical simulations, in which we include the modes of the transmission line and we use the experimental parameters of existing experimental setups. It reproduces the results derived using input-output theory in the corresponding regime and can be extended to compute dynamics where the input-output formalism cannot be straightforwardly applied. Our analysis determines the maximal storage efficiency, namely, the maximal probability to store the photon in a stable atomic excitation, in the presence of spontaneous decay and cavity parasitic losses. It further delivers the form of the laser pulse that achieves the maximal efficiency by partially compensating parasitic losses. We numerically assess the conditions under which storage based on adiabatic dynamics is preferable to non-adiabatic pulses. Moreover, we systematically determine the shortest photon pulse that can be efficiently stored as a function of the system parameters.Comment: 13 pages, 8 figure

    Serum levels of tumour associated glycoprotein (TAG 72) in patients with gynaecological malignancies.

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    Serum levels of TAG 72 were measured in 726 serum samples from patients with benign and malignant gynaecological conditions in order to evaluate the clinical usefulness of TAG 72 alone or in combination with other tumour markers. Sixty-six per cent of patients with ovarian cancer showed abnormal concentrations of TAG 72 antigen. A good correlation was also found between serial TAG 72 values and the clinical course of disease during chemotherapy and follow-up. In cervical and endometrial cancer abnormal TAG 72 values occurred in 23% and 14% of cases, while none of the patients with breast cancer had abnormal TAG 72 levels. Among patients with benign disease only one out of 12 patients (8%) with benign ovarian tumours and one of 15 patients with uterine fibromyomatosis (7%) showed high TAG 72 serum levels. However, the determination of TAG 72 did not increase the sensitivity of CA 125 and squamous cell carcinoma antigen (SCC), in ovarian and cervical cancer, respectively. The systemic administration of recombinant interferon alpha-2b to 15 patients with ovarian cancer and different basal levels of TAG 72 did not increase serum levels of the antigen

    Evaluating Filtering Strategies for Decentralized Handover Prediction in the Wireless Internet

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    The rapid diffusion of heterogeneous forms of wireless connectivity is pushing the tremendous growth of the commercial interest in mobile services, i.e., distributed applications to portable wireless terminals that roam during service provisioning. In the case of both location-dependent mobile services and mobile services with session continuity requirements, there is a growing need for decentralized and lightweight solutions to predict cell handovers, in order to enable proactive service management operations that anticipate actual terminal reconnections at their newly visited cells. The paper discusses how to predict client handovers between IEEE 802.11 cells in a portable and completely decentralized way, only by exploiting RSSI monitoring and with no need of external global positioning systems. In particular, the paper focuses on proposing and comparing different filtering techniques for mitigating Received Signal Strength Indication abrupt fluctuations. Experimental results point out that i) filtering techniques can relevantly improve the efficiency and effectiveness of handover prediction, and ii) the choice of the most appropriate filtering solution to adopt should be made at provisioning time depending on specific service/system requirements, e.g., privileging minimum overhead vs. greater prediction proactivity

    A tutorial on optimal control and reinforcement learning methods for quantum technologies

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    Quantum Optimal Control is an established field of research which is necessary for the development of Quantum Technologies. In recent years, Machine Learning techniques have been proved useful to tackle a variety of quantum problems. In particular, Reinforcement Learning has been employed to address typical problems of control of quantum systems. In this tutorial we introduce the methods of Quantum Optimal Control and Reinforcement Learning by applying them to the problem of three-level population transfer. The jupyter notebooks to reproduce some of our results are open-sourced and available on github1

    A possible role of fzd10 delivering exosomes derived from colon cancers cell lines in inducing activation of epithelial–mesenchymal transition in normal colon epithelial cell line

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    Exosomes belong to the family of extracellular vesicles released by every type of cell both in normal and pathological conditions. Growing interest in studies indicates that extracellular vesicles, in particular, the fraction named exosomes containing lipids, proteins and nucleic acid, represent an efficient way to transfer functional cargoes between cells, thus combining all the other cell–cell interaction mechanisms known so far. Only a few decades ago, the involvement of exosomes in the carcinogenesis in different tissues was discovered, and very recently it was also observed how they carry and modulate the presence of Wnt pathway proteins, involved in the carcinogenesis of gastrointestinal tissues, such as Frizzled 10 protein (FZD10), a membrane receptor for Wnt. Here, we report the in vitro study on the capability of tumor-derived exosomes to induce neoplastic features in normal cells. Exosomes derived from two different colon cancer cell lines, namely the non-metastatic CaCo-2 and the metastatic SW620, were found to deliver, in both cases, FZD10, thus demonstrating the ability to reprogram normal colonic epithelial cell line (HCEC-1CT). Indeed, the acquisition of specific mesenchymal characteristics, such as migration capability and expression of FZD10 and markers of mesenchymal cells, was observed. The exosomes derived from the metastatic cell line, characterized by a level of FZD10 higher than the exosomes extracted from the non-metastatic cells, were also more efficient in stimulating EMT activation. The overall results suggest that FZD10, delivered by circulating tumor-derived exosomes, can play a relevant role in promoting the CRC carcinogenesis and propagation
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