Intent-Based Orchestration for Application Relocation in a 5G Cloud-native Platform

The need of mobile network operators for cost-effectiveness is driving 5G and beyond networks towards highly flexible and agile deployments to adapt to dynamic and resource-constrained scenarios while meeting a myriad of user network stakeholders' requirements. In this setting, we consider that zero-touch orchestration schemes based on cloud-native deployments equipped with end-to-end monitoring capabilities provide the necessary technology mix to be a solution candidate. This demonstration, built on top of an end-to-end cloud-native 5G experimental platform with over-the-air transmissions, shows how dynamic orchestration can relocate container-based end-user applications to fulfil intent-based requirements. Accordingly, we provide an experimental validation to showcase how the platform enables the desired flexible and agile 5G deployments

Decorative PVD coatings as an enviromentally clean alternative to chrome plating

The objective of this work is to conduct applied research and development to demonstrate yhat metal or ceramic coatings deposited by Physical Vapor Deposition (PVD)are equivalent or superior in peformance and are a cost-effective alternative to chrome plating in decorative applications. Chromium plating is comercially used to produce wear-resistant and decorative coatings, but the plating bath contains hexavalent chromium, which has adverse health and environmental effects. The present study describes and compares the mechanical and tribological properties of TiN,AlTiN, ZrCN coatings deposited by CAPVD (cathodic arc plasma pgysical vapor deposition), on nickel plated aluminium substrates. The properties of the above mentioned PVD coatings have been compared with the properties of conventional chromium plating.Peer Reviewe

Formability of the 5754-aluminum alloy deformed by a modified repetitive corrugation and straightening process

Sheets of 5754-aluminum alloy processed by a modified repetitive corrugation and straightening (RCS) process were tested in order to measure their formability. For this purpose, forming limit curves were derived. They showed that the material forming capacity decreased after being processed by RCS. However, they kept good formability in the initial stages of the RCS process. The formability study was complemented with microstructural analysis (derivation of texture) and mechanical tests to obtain the strain-rate sensitivity. The texture analysis was done by employing X-ray diffraction, obtaining pole figures, and the orientation distribution function. It was noticed that the initial texture was conserved after successive RCS passes, but the intensity dropped. RCS process did not induce ß-fiber, contrary to common deformation process. The strain-rate sensitivity coefficient was measured through tensile tests at different temperatures and strain rates; the coefficient of the samples processed after one and two passes were still relatively high, indicating the capacity to delay necking, in agreement with the good formability observed in the initial passes of the RCS processPeer ReviewedPostprint (published version

Cobalt free metallic binders for HVOF thermal sprayed wear resistant coatings

Thermal sprayed HVOF WC-based cermet coatings containing various metallic binders have been used in several different applications in industries that require abrasive sliding wear resistance, such as hydraulic pistons, shafts or bearings. The potential dangerousness and cost increase off cobalt-based metallic binders, underlining the challenge in reducing reliance on this metal as metallic binder in wear resistant coatings. The present work aims to study the feasibility of WC-NiMoCrFeCo, WC-CrC-Ni and WC-FeCrAl coatings, in contrast to conventional WCCoCr, by evaluating their microstructure, mechanical, tribological and corrosion resistance properties. Commercially feedstock powders were sprayed onto steel plates using a kerosene-fuelled HVOF WokaJet 400 gun. The WC-CoCr coating shows a slightly highest hardness than WC-NiMoCrFeCo and WC-FeCrAl coatings, showing a slight trend towards an increase in the wear rate as the coating hardness decreases. The WC-CrC-Ni coating is significantly the softest and least wear resistant coating, as a consequence of the presence of a high percentage of lower hardness CrC particles. Nevertheless, this coating shows similar corrosion resistance to of conventional WC-CoCr coating, while the WC-NiMoCrFeCo and WC-FeCrAl coatings show a slightly worse corrosion resistancPeer ReviewedPostprint (published version

X-GRL: An Empirical Assessment of Explainable GNN-DRL in B5G/6G Networks

The rapid development of artificial intelligence (AI) techniques has triggered a revolution in beyond fifth-generation (B5G) and upcoming sixth-generation (6G) mobile networks. Despite these advances, efficient resource allocation in dynamic and complex networks remains a major challenge. This paper presents an experimental implementation of deep reinforcement learning (DRL) enhanced with graph neural networks (GNNs) on a real 5G testbed. The method addresses the explainability of GNNs by evaluating the importance of each edge in determining the model's output. The custom sampling functions feed the data into the proposed GNN-driven Monte Carlo policy gradient (REINFORCE) agent to optimize the gNodeB (gNB) radio resources according to the specific traffic demands. The demo demonstrates real-time visualization of network parameters and superior performance compared to benchmarks.Comment: 3 pages, 8 figure

Effect of oxygen/fuel ratio on the in-flight particle parameters and properties of HVOF WC–CoCr coatings

High Velocity Oxy-Fuel (HVOF) spray techniques can produce high performance alloy and cermet coatings for applications that require wear resistant surfaces. In HVOF spraying heat is produced by burning mixtures of oxygen and fuel, mainly hydrogen, kerosene, propane, propylene, natural gas or acetylene. In these processes, the particle velocity and temperature determine the resultant coating properties and in many cases enables a better understanding of the process. The aim of this study is to investigate influences of different oxygen/fuel ratios on velocity and temperature of flying particles as well as properties of the HVOF thermal sprayed WC-CoCr coatings. In this work the feedstock powders were thermally sprayed by two different variants of the high velocity oxy-fuel process, in which the fuels were hydrogen and kerosene. Particle parameters were recorded just prior to impact on the substrate using in-flight particle diagnostic tool Accuraspray-g3®. Detailed correlation of particle parameters and the coating properties is evaluated in order to deduce particle parameter ranges providing coatings with optimum properties.Postprint (published version

Rheological Behavior of the A356 Alloy in the Semisolid State at Low Shear Rates

To control the semisolid processing of aluminum alloys produced by the additive manufacturing technique, an exhaustive knowledge of their rheological behavior is required. In the semisolid state, metallic materials can show rheological characteristics similar to those of polymers, so semisolid state shaping is one of the currently considered routes for additive manufacturing with metallic materials. In this work, an approximation of the rheological control of the A356 aluminum alloy for its subsequent 3D manufacturing was carried out at a very low shear rate. A continuous cooling rheometer was designed and used, evaluating the influence of different process parameters on the viscosity variation of the aluminum alloy in the semisolid state. The results show an anomalous flow variation, indicating dilatant, and not thixotropic behavior, for very low shear rates.Peer ReviewedPostprint (published version

Synergy-COPD: a systems approach for understanding and managing chronic diseases.

Chronic diseases (CD) are generating a dramatic societal burden worldwide that is expected to persist over the next decades. The challenges posed by the epidemics of CD have triggered a novel health paradigm with major consequences on the traditional concept of disease and with a profound impact on key aspects of healthcare systems. We hypothesized that the development of a systems approach to understand CD together with the generation of an ecosystem to transfer the acquired knowledge into the novel healthcare scenario may contribute to a cost-effective enhancement of health outcomes. To this end, we designed the Synergy-COPD project wherein the heterogeneity of chronic obstructive pulmonary disease (COPD) was addressed as a use case representative of CD. The current manuscript describes main features of the project design and the strategies put in place for its development, as well the expected outcomes during the project life-span. Moreover, the manuscript serves as introductory and unifying chapter of the different papers associated to the Supplement describing the characteristics, tools and the objectives of Synergy-COP

Decorartive PVD coatings as an environmentally clean alternative to chrome plating

Peer ReviewedPostprint (published version