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In this study, a methodology for assessing the thickness of titanium nitride (TiN) coatings by energy dispersive X-ray spectroscopy (EDS) in the scanning electron microscope is explored. A standardless method is applied, where the film thickness (th) is related to the microscope accelerating voltage (V0), the type of substrate and the ratio between the more intense peaks in the EDS spectrum, arising from both the substrate and the coating (afterwards called the I-ratio, IR). Three different substrates covered with TiN were studied, namely, silicon, glass, and stainless steel. Monte Carlo simulations enabled to state an analytic equation, which allows assessing the coating thickness as follows:th=thcr⋅exp[−βIR1/n]where IR = Iksubstrate/Ikcoating, thcr (critical thickness) is the largest coating thickness, which is assessable at a fixed V0, β is a multiplication factor, and n is an exponent, where thcr, β and n are assessable from V0 and substrate type. Interpolation via the equation presented, using reference thicknesses, allowed thickness predictions with around 80% of datapoints differing less than around 2% from the reference value. A procedure for detecting variations as low as 1.0% in coating thickness regarding the nominal thickness is presented.

The Spanish Ministry of Defense is currently attempting to reduce the amount of energy that is consumed by its military bases and has therefore raised concerns about how to make their facilities more energy efficient. To fulfill this objective, the Spanish army has developed various studies and projects, as well as a technical prescription sheet that defines the thermal transmittance values of the materials that are to be used to construct the different elements of the containers that make up the temporary housing units at Spanish military camps. Both governments and private entities have developed initiatives that are aimed at improving the energy efficiency of buildings, which are classified into two groups: those aimed at the development of mandatory building codes and those that are based on voluntary certification programs. The use of passive strategies is one of the key actions that is being implemented to achieve the NZEB category, as its first requirement is to be a “very low energy consumption building”. This paper compares the energy efficiency requirements of the tents and containers that are used in military camps and the energy-efficient design requirements that are demanded by the energy efficiency standards for buildings in the civil sector. Through this comparison, we determine how energy efficient the current living spaces in military camps are in order to define strategies that can be implemented to improve the design requirements of these living spaces so to reduce the consumption and operation logistics and to improve both operability and safety in military camp facilities.

This study analyzes future synergies between the Oil and Gas (O&G) and renewables sectors in a Danish context and explores how exploiting these synergies could lead to economic and environmental benefits. We review and highlight relevant technologies and related projects, and synthesize the state of the art in offshore energy system integration. All of these preliminary results serve as input data for a holistic energy system analysis in the Balmorel modeling framework. With a timeframe out to 2050 and model scope including all North Sea neighbouring countries, this analysis explores a total of nine future scenarios for the North Sea energy system. The main results include an immediate electrification of all operational Danish platforms by linking them to the shore and/or a planned Danish energy island. These measures result in cost and CO2 emissions savings compared to a BAU scenario of 72% and 85% respectively. When these platforms cease production, this is followed by the repurposing of the platforms into hydrogen generators with up to 3.6 GW of electrolysers and the development of up to 5.8 GW of floating wind. The generated hydrogen is assumed to power the future transport sector, and is delivered to shore in existing and/or new purpose-built pipelines. The contribution of the O&G sector to this hydrogen production amounts to around 19 TWh, which represents about 2% of total European hydrogen demand for transport in 2050. The levelized costs (LCOE) of producing this hydrogen in 2050 are around 4 €2020/kg H2, which is around twice those expected in similar studies. But this does not account for energy policies that may incentivize green hydrogen production in the future, which would serve to reduce this LCOE to a level that is more competitive with other sources., Advances in Applied Energy, 4, ISSN:2666-7924

Autonomous systems are expected to maintain a dependable operation without human intervention. They are intended to fulfill the mission for which they were deployed, properly handling the disturbances that may affect them. Underwater robots, such as the UX-1 mine explorer developed in the UNEXMIN project, are paradigmatic examples of this need. Underwater robots are affected by both external and internal disturbances that hamper their capability for autonomous operation. Long-term autonomy requires not only the capability of perceiving and properly acting in open environments but also a sufficient degree of robustness and resilience so as to maintain and recover the operational functionality of the system when disturbed by unexpected events. In this article, we analyze the operational conditions for autonomous underwater robots with a special emphasis on the UX-1 miner explorer. We then describe a knowledge-based self-awareness and metacontrol subsystem that enables the autonomous reconfiguration of the robot subsystems to keep mission-oriented capability. This resilience augmenting solution is based on the deep modeling of the functional architecture of the autonomous robot in combination with ontological reasoning to allow self-diagnosis and reconfiguration during operation. This mechanism can transparently use robot functional redundancy to ensure mission satisfaction, even in the presence of faults.

This contribution reports on an experimental polishing procedure, that is comprised of early grinding in Al2O3 slurries and late polishing in colloidal silica, which is used for preparing the nitrided region of a plasma nitrided austenitic stainless steel, for crystallographic analysis via electron backscatter diffraction (EBSD). The suitability of the polished surfaces for conducting EBSD characterization was assessed through an analysis of both the surface roughness (appraised by atomic force microscopy) and the quality of the Kikuchi diffraction patterns. We observed that as-nitrided virgin surfaces were not suitable for EBSD characterization, due to intense surface roughening, which was induced by the nitriding process itself. At the subsurface region, exposed by on-top mechanical polishing, the flatter nature of the polished surfaces allowed the acquisition of EBSD patterns with enough quality for microtexture analysis. A resolution of 100 nm in the total removed layer was attainable via careful control of the polishing parameters. Close parallelism between the polished and original surfaces was verified.

Resumen Introduccion La situacion de crisis generada por la COVID-19 y las medidas adoptadas han generado cambios sociales en las dinamicas normales de la poblacion general y en especial para los trabajadores de la salud, que se encuentran en atencion del paciente con infeccion sospechada o confirmada. Estudios recientes han detectado en ellos sintomas depresivos y ansiosos y sindrome de burnout, afecciones personales y sociales que alteran su capacidad de respuesta durante la emergencia sanitaria. El objetivo es generar recomendaciones de promocion y proteccion de la salud mental de los trabajadores y equipos de salud dispuestos como primera linea de atencion en la emergencia sanitaria por COVID-19. Metodos Se realizo una busqueda rapida de literatura en PubMed y Google Scholar, y un consenso de expertos iterativo y mediante consulta electronica, con 13 participantes de las areas de psicologia, psiquiatria y medicina; la gradacion de su fuerza y direccionalidad se realizo segun las normas internacionales del Joanna Briggs Institute. Resultados Se generaron 31 recomendaciones sobre el autocuidado del trabajador de la salud, el cuidado comunitario entre los equipos de salud, el cribado de signos de alarma en salud mental y para las instituciones sanitarias. Conclusiones Las actividades de promocion y proteccion en salud mental para el afrontamiento de la emergencia sanitaria generada por la COVID-19 en todo el mundo pueden abarcar acciones articuladas entre el trabajador, los equipos de salud y las instituciones sanitarias como parte de un cuidado integral, comunitario, corresponsable y sostenidas en el tiempo.

This paper presents an approach for implementing game theoretic decision making in combination with realistic sensory data input so as to allow an autonomous vehicle to perform maneuvers, such as lane change or merge in high traffic scenarios. The main novelty of this work, is the use of realistic sensory data input to obtain the observations as input of an iterative multi-player game in a realistic simulator. The game model allows to anticipate reactions of additional vehicles to the movements of the ego-vehicle without using any specific coordination or vehicle-to-vehicle communication. Moreover, direct information from the simulator, such as position or speed of the vehicles is also avoided.The solution of the game is based on cognitive hierarchy reasoning and it uses Monte Carlo reinforcement learning in order to obtain a near-optimal policy towards a specific goal. Moreover, the game proposed is capable of solving different situations using a single policy. The system has been successfully tested and compared with previous techniques using a realistic hybrid simulator, where the ego-vehicle and its sensors are simulated on a 3D simulator and the additional vehicles’ behavior is obtained from a traffic simulator.

Stainless steel films were obtained from an 316L target onto steel substrates by pulsed-DC magnetron sputtering, varying the pulse frequency from non-pulsed (conventional DC) up to 350 kHz. Experiments were carried out with a substrate temperature of 673 K and time-averaged electrical power density of 15.3 W cm−2. Stabilization of the face-centered cubic, but not the body-centered cubic phase was observed under pulsed-DC compared to conventional DC. This was attributed to increased average adatom energy under pulsed-DC.

This contribution presents a theoretical discussion on phase hierarchy stability between face-centered cubic (FCC), austenite, and body-centered cubic (BCC), ferrite, lattice structures of stainless steel (SS) films that are sputter-deposited from austenitic targets under non-reactive atmospheres. Data published in literature on both phase characterization and chemical composition of diverse SS films are interpreted anew in this contribution in the light of lattice stability thermodynamic simulations. For films obtained from 304 and 316 steel targets, thermodynamic simulations predict that the ferrite phase is more stable than the austenite phase at low thermal energies. In contrast, simulations forecast thermodynamic stability at low thermal energies of the austenite phase in films that are sputtered from 330 steel targets. The criterion of lattice stability reveals that structures observed in the experiments cannot be described comprehensively by thermodynamic states where either full atomic partitioning among phases is established or zero atomic partitioning takes place. Thereby, a description of an equilibrium with incomplete atomic partitioning is proposed here, with the aim of depicting the structures reported in the literature. Such an equilibrium with incomplete atomic partitioning adequately describes the gradual destabilization of ferrite and the increased fraction of austenite (up to fully austenitic structures), when either the substrate heating is intensified, or the Ni content of the alloy is increased, with an 73Fe18Cr9Ni, wt%, initial alloy as a basis.

In this study, we report on phase fractions and nitrogen distribution among structure components of stainless steel films that are sputter-deposited from an 316L target under Ar + N 2 atmospheres. As N 2 flow rate was increased were obtained samples with the following structures: BCC (N-lean), BCC plus FCC (between 2.0 and 6.0 N at.%), and fully FCC (11.5 N at.% and higher N-contents). Experiments under two different sets of deposition conditions were carried out, where the actual relationship between phase fractions and N 2 flow rate showed differences among the two experimental sets of samples. N-content in the FCC phase in duplex structures varied between 3 and 9 at.%. An equilibrium with constrained atomic partitioning of substitutional species and full atomic partitioning of nitrogen was proposed, with the aim of depicting the structures observed.

UNS S31603 stainless steel (SS) substrates were covered by reactive magnetron-sputtering with protective SS coatings of the same steel specification. A mechanical characterization study (through nano-, micro- and macro-hardness tests) of samples obtained under two different sputtering conditions and varying the N2 gas flow rate was carried out. This contribution aimed at appraising the effects of varying the nitrogen flow rate on hardness, elastic modulus, and susceptibility to indentation-induced crack formation of the coated SSs. Nitrogen-free samples displayed body-centered cubic (BCC) films with 9.0-9.4 GPa hardness and 203-206 GPa elastic modulus, while their susceptibility to indentation-induced cracking varied between superior and moderated among the two sets of sputtering conditions studied. Samples alloyed with 4-6 N at-% displayed a predominantly face-centered cubic (FCC) structure, 9.4 GPa hardness, 196-218 GPa elastic modulus, and superior resistance to crack formation. Samples with 11.5-22.0 N at-% were fully composed of the FCC structure, displayed 12.4-15.2 GPa hardness, 188-193 GPa elastic modulus, and moderated resistance to indentation-induced crack formation. Samples with 47.0 N at-% displayed FCC compound nitride structure, for which hardness and elastic modulus were 8.1 GPa and 139 GPa, respectively. These samples displayed low resistance to crack formation.

This paper presents a game theoretic decision making process for autonomous vehicles. Its goal is to provide a solution for a very challenging task: the merge manoeuvre in high traffic scenarios. Unlike previous approaches, the proposed solution does not rely on vehicle-to-vehicle communication or any specific coordination, moreover, it is capable of anticipating both the actions of other players and their reactions to the autonomous vehicle’s movements.

The constant growth of the population with mobility impairments has led to the development of several gait assistance devices. Among these, smart walkers have emerged to provide physical and cognitive interactions during rehabilitation and assistance therapies, by means of robotic and electronic technologies. In this sense, this paper presents the development and implementation of a human&ndash, robot&ndash, environment interface on a robotic platform that emulates a smart walker, the AGoRA Walker. The interface includes modules such as a navigation system, a human detection system, a safety rules system, a user interaction system, a social interaction system and a set of autonomous and shared control strategies. The interface was validated through several tests on healthy volunteers with no gait impairments. The platform performance and usability was assessed, finding natural and intuitive interaction over the implemented control strategies.

International audience; This paper presents a novel tool capable of collecting thermal signatures inside a building by using low-cost IR temperature sensors mounted on-board an aerial platform. The proposed system aims to facilitate the detection of heat loss inside buildings, which is a key aspect for improving energy efficiency in large commercial or industrial buildings. Current detection systems usually require manual labor as well as the use of expensive instrumentation. The proposed system on the other hand, relies on the use of a small unmanned aerial vehicle carrying low-cost thermopile IR sensors. Moreover, the system delivers a fast temperature sensing scheme and it provides coverage to inaccessible areas, thus overcoming the limitations of current mobile platforms which use ground robots. Different experiments were carried out in order to assess the behavior of the sensors as well as to validate the full system. Moreover, the hypothesis that thermopile IR sensors can be used to track temperature signature on-the-fly is validated experimentally with the use of the proposed system over different targets.

Flexible sector coupling of heat and electricity is a well-documented way of facilitating efficient and renewables-based energy systems. Heating is characterised by substitutable heat sources, where some facilitate flexibility and sector coupling, while others do not. Earlier studies indicate sector coupling hindrances from competing biomass-based heat sources. The scientific contribution of this study is an investigation of heat source substitution as a general route to sector coupling. We explore the impacts of constraining biomass use, applying the Danish heat sector as a case, to see impacts on indicators such as power-to-heat deployment. We do so by introducing taxes on biomass use, ban biomass boilers and entirely prohibit use of biomass. These constraints are modelled in the Balmorel model. The results show that system costs decrease along with biomass use. Power-to-heat use, CO2-emissions, tax- and electricity tariff revenue and end-user heat cost increase, in some cases substantially. It appears that a CO2 price signal is sufficient to obtain CO2-reductions, whereas other motivations, including increased electrification of the heating sector, may justify constraints on biomass use.