Accessibility in 360º video players

Accessibility is a key requirement for any multimedia tool and application. With the current trend towards immersive experiences, such as Virtual Reality (VR) and 360o video, it becomes key that these environments are adapted to be fully accessible. However, until recently the focus has been mostly on adapting the existing techniques to fit immersive displays, rather than considering new approaches for accessibility designed specifically for these increasingly relevant media experiences. This paper surveys a wide range of 360o video players and examines the features they include for dealing with accessibility, such as Subtitles, Audio Description, Sign Language, User Interfaces and other interaction features, like voice control and support for multi-screen scenarios. These features have been chosen based on guidelines from standardization contributions, like in the World Wide Web Consortium (W3C) and the International Communication Union (ITU), and from research contributions for making 360º video consumption experiences accessible. The in-depth analysis has been part of a research effort towards the development of a fully inclusive and accessible 360º video player. The paper concludes by discussing how the newly developed player has gone above and beyond the existing solutions and guidelines, by providing accessibility features that meet the expectations for a widely used immersive medium, like 360º video

Prediction of the annual performance of marine organic Rankine cycle power systems

The increasing awareness about the environmental impact of shipping and the increasingly stricter regulations introduced by the International Maritime Organization are driving the development of solutions to reduce the pollutant emissions from ships. While some previous studies focused on the implementation of a specific technology, others considered a wider perspective and investigated the feasibility of the integration of various technologies on board vessels. Among the screened technologies, organic Rankine cycle (ORC) power systems represent a viable solution to utilize the waste heat contained in the main engine exhaust gases to produce additional power for on board use. The installation of ORC power systems on board ships could result in a reduction of the CO2 emissions by 5 – 10 %. Although a number of methods to derive the optimal design of ORC units in marine applications have been proposed, these methods are complex, computationally expensive and require specialist knowledge to be included as part of a general optimization procedure to define the optimal set of technologies to be implemented on board a vessel. This study presents a novel method to predict the performance of ORC units installed on board vessels, based upon the characteristics of the main engine exhaust gases and the ship sailing profile. The method is not computationally intensive, and is therefore suitable to be used in the context of large optimization problems, such as holistic optimization and evaluation of a ship performance given the operational profile, weather and route. The model predicted the annual energy production of two case studies with an accuracy within 4

A computational methodology to account for the liquid film thickness evolution in Direct Numerical Simulation of prefilming airblast atomization

Prefilming airblast atomization is widely used in aero engines. Fundamental studies on the annular configuration of airblast atomizers are difficult to realize. For this reason, researchers focused on planar configurations. In this regard, the Karlsruhe Institute of Technology (KIT) developed a test rig to conduct experimental activities, conforming a large database with results for different conditions. Such data allow validation of two-phase flow calculations concerning primary atomization on these devices. The present investigation proposes a Direct Numerical Simulation (DNS) on the KIT planar configuration through the Volume of Fluid (VOF) method within the PARIS code. The novelty compared to DNS reported in the literature resides in the use of a boundary condition that accounts not only for the gas inflow turbulence but also for the spatio-temporal evolution of the liquid film thickness at the DNS inlet and its effect on turbulence. The proposed methodology requires computing precursor single-phase and two-phase flow Large-Eddy Simulations. Results are compared to DNS that only account for a constant (both timewise and spanwise) liquid film thickness at the domain inlet, validating the workflow. The proposed methodology improves the qualitative description of the breakup mechanism, as its different stages (liquid accumulation behind the prefilmer edge, bag formation, bag breakup, ligament formation and ligament breakup) coexist spanwise for a given temporal snapshot. This implies more continuous atomization than the one predicted by the constant film thickness case, which showed the same breakup stage to be present along the prefilmer span for a given instant and led to a more discretized set of atomization events. The proposed workflow allows quantifying the influence of the liquid film flow evolution above the prefilmer on primary breakup frequency and atomization features.Comment: Preprint submitted to International Journal of Multiphase Flo

Seasonal performance assessment of sanitary hot water production systems using propane and CO2 heat pumps

[EN] This paper presents an experimental analysis and performance evaluation of a ground source heat pumpsystem providing heating/cooling to an office building, located at the Universitat Politècnica de Valènciain Spain. The experimental data and a detailed description of the analysis tool used were presented ina previous paper for the first six operational years. This paper provides the adaptation of such analysistool to the new configuration (heat pump with two compressors working in tandem), and provides anupdated complete reference data sets over more than eleven years which can be used by researchers formodel validation purposes.The work of M. Tammaro on electric heat pumps is supported by the Next Heat Pump Generation project (funded by the European Commission in the 7th Framework Programme, grant number 307169 - European Heat Pump Association, 2013), which is gratefully acknowledged.Tammaro, M.; Montagud, C.; Corberán, J.; Mauro, A.; Mastrullo, R. (2017). Seasonal performance assessment of sanitary hot water production systems using propane and CO2 heat pumps. International Journal of Refrigeration. 74:222-237. https://doi.org/10.1016/j.ijrefrig.2016.09.0262222377

A novel TRNSYS type of a coaxial borehole heat exchanger for both short and mid term simulations: B2G model

[EN] A dynamic model of a ground source heat pump system is a very useful tool in order to optimize its design and operation. In order to fairly predict the performance of such a system, the dynamic evolution of the fluid entering the heat pump and coming from the borehole heat exchanger (BHE) must be accurately reproduced not only in the long term but also in the short-mid term operating conditions, as it directly affects the coefficient of performance of the heat pump unit. In this context, the B2G model was developed to reproduce the short-term dynamic evolution of the fluid temperature inside the BHE. This work presents the new upgraded version of the B2G dynamic model for a coaxial BHE, which includes several new features to better reproduce not only the short-term but also the mid-term behaviour of the BHE. For that purpose, the model of the surrounding ground has been improved: vertical heat conduction in the grout and ground, heterogenous ground with different layers, and a higher number of ground nodes in the thermal network considered in the model were added, which are automatically located by means of polynomial correlations for any type of ground, geometry and operating conditions. This novel approach has been implemented in TRNSYS for accurately modelling the dynamic behaviour of a coaxial BHE with low computational cost (2.5¿s for a 24¿h simulation period in a modern computer). The model has been validated against experimental data from a dual source heat pump installation in Tribano (Padua, Italy) and has proven capable of accurately reproducing the short-mid term (up to five days) behaviour of the BHE, with a deviation lower than 0.12¿K.The present work has been supported by the European Community Horizon 2020 Program for European Research and Technological Development (2014-2020) inside the framework of the project 656889 –GEOTeCH (Geothermal Technology for Economic Cooling and Heating) and by the Generalitat Valenciana inside the program “Ayudas para la contratación de personal investigador en formación de carácter predoctoral (ACIF/2016/131)”.Cazorla-Marín, A.; Montagud- Montalvá, C.; Tinti, F.; Corberán, JM. (2019). A novel TRNSYS type of a coaxial borehole heat exchanger for both short and mid term simulations: B2G model. Applied Thermal Engineering. 164(114500):1-15. https://doi.org/10.1016/j.applthermaleng.2019.114500S11516411450

Impact of Social Media on TV Content Consumption: New Market Strategies, Scenarios and Trends

The mass adoption of Social Media together with the proliferation and widely usage of multi-connected companion devices have tremendously transformed the TV/video consumption paradigm, opening the door to a new range of possibilities. This Special Issue has aimed at analyzing, from different point of views, the impact of Social Media and social interaction tools on the TV/video consumption area. The targeted topics of this Special Issue and a general overview of the accepted articles are provided in this Guest Editorial

Role of mTOR-regulated autophagy in spine pruning defects and memory impairments induced by binge-like ethanol treatment in adolescent mice

Adolescence is a brain maturation developmental period during which remodeling and changes in synaptic plasticity and neural connectivity take place in some brain regions. Different mechanism participates in adolescent brain maturation, including autophagy that plays a role in synaptic development and plasticity. Alcohol is a neurotoxic compound and its abuse in adolescence induces neuroinflammation, synaptic and myelin alterations, neural damage and behavioral impairments. Changes in synaptic plasticity and its regulation by mTOR have also been suggested to play a role in the behavioral dysfunction of binge ethanol drinking in adolescence. Therefore, by considering the critical role of mTOR in both autophagy and synaptic plasticity in the developing brain, the present study aims to evaluate whether binge ethanol treatment in adolescence would induce dysfunctions in synaptic plasticity and cognitive functions and if mTOR inhibition with rapamycin is capable of restoring both effects. Using C57BL/6 adolescent female and male mice (PND30) treated with ethanol (3 g/kg) on two consecutive days at 48-hour intervals over 2 weeks, we show that binge ethanol treatment alters the density and morphology of dendritic spines, effects that are associated with learning and memory impairments and changes in the levels of both transcription factor CREB phosphorylation and miRNAs. Rapamycin administration (3 mg/kg) prior to ethanol administration restores ethanol-induced changes in both plasticity and behavior dysfunctions in adolescent mice. These results support the critical role of mTOR/autophagy dysfunctions in the dendritic spines alterations and cognitive alterations induced by binge alcohol in adolescence

Development and Experimental Validation of a TRNSYS Dynamic Tool for Design and Energy Optimization of Ground Source Heat Pump Systems

[EN] Ground source heat pump (GSHP) systems stand for an efficient technology for renewable heating and cooling in buildings. To optimize not only the design but also the operation of the system, a complete dynamic model becomes a highly useful tool, since it allows testing any design modifications and different optimization strategies without actually implementing them at the experimental facility. Usually, this type of systems presents strong dynamic operating conditions. Therefore, the model should be able to predict not only the steady-state behavior of the system but also the short-term response. This paper presents a complete GSHP system model based on an experimental facility, located at Universitat Politècnica de València. The installation was constructed in the framework of a European collaborative project with title GeoCool. The model, developed in TRNSYS, has been validated against experimental data, and it accurately predicts both the short- and long-term behavior of the system.The present work has been supported by the FP7 European project "Advanced ground source heat pump systems for heating and cooling in Mediterranean climate" (GROUND-MED), and by the Generalitat Valenciana inside the program "Ayudas para la contratacion de personal investigador en formacion de caracter predoctoral (ACIF/2016/131)". A particular mention is given to the European Community Horizon 2020 Program for European Research and Technological Development (2014-2020), who has covered the costs to publish this work and funded part of this research inside the framework of the project 656889-GEOTeCH (Geothermal Technology for Economic Cooling and Heating).Ruiz-Calvo, F.; Montagud, C.; Cazorla-Marín, A.; Corberán, JM. (2017). Development and Experimental Validation of a TRNSYS Dynamic Tool for Design and Energy Optimization of Ground Source Heat Pump Systems. Energies. 10 (10)(10):1-21. https://doi.org/10.3390/en10101510S12110 (10)1

Wersync: A WEB-BASED PLATFORM FOR DISTRIBUTED MEDIA SYNCHRONIZATION AND SOCIAL INTERACTION

This paper presents Wersync, which is an adaptive and accurate web-based platform that enables distributed media synchronization and social interaction across remote users. By using Wersync, users can create or join on-going sessions for concurrently consuming the same media content with other remote users in a synchronized manner. Besides, social interaction is provided by sharing the navigation control commands and by integrating synchronized text chat channels. Additionally, two social presence mechanisms have been added to stimulate the participation of external users in on-going sessions on Wersync. By exclusively relying on standard web-based technologies, this platform can guarantee cross-network, cross-platform and crossdevice support, which is a key point in the current heterogeneous media delivery ecosystem

Energy and techno-economic assessment of the effect of the coupling between an air source heat pump and the storage tank for sanitary hot water production

[EN] Heat pumps are proved to be a highly efficient technology for sanitary hot water production. However, when installing them coupled with the storage tank, an inefficiency up to 30% can be introduced in the system since this coupling cannot be direct according to EN 1717:2000; in order to prevent from any potential pollution of potable water in case of a refrigerant leakage. This research work evaluates three types of indirect coupling in the case of an air source heat pump system for sanitary hot water production: a coil heat exchanger inside the storage tank (CC), an intermediate heat exchanger between the tank and the heat pump (EHXC) and a double wall condenser (DWCC). A techno-economic assessment was carried out for the representative climate conditions around Europe. Results show that the DWCC is always the most efficient and cost-effective solution with a 3.66% lower energy efficiency than the direct coupling (Base Case), whereas the CC is not only the less efficient solution (27.1% lower than the Base Case) but also the less cost-effective, with a 50% lower net present value than the DWCC.The authors acknowledge the financial support provided by the project "ENE2017-83665-C2-1-P" and the programme 'Formation de Profesorado Universitario (FPU15/03476)', funded by the "Ministerio de Ciencia, Innovation y Universidades" of Spain.Masip, X.; Cazorla-Marín, A.; Montagud- Montalvá, C.; Marchante-Avellaneda, J.; Barceló Ruescas, F.; Corberán, JM. (2019). Energy and techno-economic assessment of the effect of the coupling between an air source heat pump and the storage tank for sanitary hot water production. Applied Thermal Engineering. 159(113853):1-8. https://doi.org/10.1016/j.applthermaleng.2019.113853S1815911385