Nonlinear model predictive control for hydrogen production in an ethanol steam reformer with membrane separation

© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThis paper presents a new Nonlinear Model Predictive Control (NMPC) design for an Ethanol Steam Reformer with Pd-Ag membrane separation stage. The reformer is used to produce pure hydrogen able to feed a Proton Exchange Membrane Fuel Cell. Mass and energy balances are used to obtain the nonlinear dynamic model of both the reforming and the separation stages. Constraints, system nonlinearities and flexible cost function are the main reasons to select an NMPC controller, which is tested against the ordinary differential equations as simulation model, and has an internal model based on the sample data technique.Accepted versio

Internet and communications as elements for CIDT and Torture. Initial reflections in an unexplored field

The internet was once seen as a new and definitive window to freedom and a world without torture. There is however, another less obvious but perhaps more notorious side: torturous environments can also be created through the internet; a place where individu- als may be targeted for discrimination, coer- cion or control.There is a dearth of academic research and theoretical developments in this very new area of knowledge and this Edito- rial will review and reflect on various aspects, thereby suggesting possible lines of research

Identification of N-terminal protein acetylation and arginine methylation of the voltage-gated sodium channel in end-stage heart failure human heart

The α subunit of the cardiac voltage-gated sodium channel, Naᵥ1.5, provides the rapid sodium inward current that initiates cardiomyocyte action potentials. Here, we analyzed for the first time the post-translational modifications of Naᵥ1.5 purified from end-stage heart failure human cardiac tissue. We identified R526 methylation as the major post-translational modification of any Naᵥ1.5 arginine or lysine residue. Unexpectedly, we found that the N terminus of Naᵥ1.5 was: 1) devoid of the initiation methionine, and 2) acetylated at the resulting initial alanine residue. This is the first evidence for N-terminal acetylation in any member of the voltage-gated ion channel superfamily. Our results open the door to explore Naᵥ1.5 N-terminal acetylation and arginine methylation levels as drivers or markers of end-stage heart failure

Cómo guardar el mundo digital en un COFRE (COnservamos para el Futuro Recursos Electrónicos)

La preservació digital ha esdevingut una de les àrees d’interès i un repte per a les institucions que conserven patrimoni. Arreu del món, les institucions, sovint de caràcter nacional, han posat en marxa iniciatives per fer-hi front i explorar-ne solucions. Al nostre país, la Biblioteca de Catalunya, l’any 2008, va iniciar el disseny d’un repositori digital de preservació anomenat COFRE (COnservem per al Futur Recursos Electrònics), que des de 2010 es troba operatiu. COFRE inicialment va ser impulsat per cobrir les necessitats pròpies de la Biblioteca, si bé sempre ha tingut la voluntat i la visió de poder acollir altres institucions i oferir així un servei de país. L’article en descriu l’origen, el contingut, els processos, les característiques tècniques i la infraestructura.Digital preservation has become an area of interest and a challenge for the institutions dedicated to preserving heritage. Worldwide, institutions, often national ones, have launched initiatives to address the issue and to explore solutions. In Ca-talonia, the Biblioteca de Catalunya began designing a digital preservation repository known as COFRE (COnservem per al Futur Recursos Electrònics = Preserving electronic resources for the future) in 2008. It has been in operation since 2010. COFRE was initially promoted to meet the needs of the library itself, though it has always held the intention and vision to house other institutions, thereby providing a service for the country. The article describes the background, content, proces-ses, technical features and infrastructure of the repository.La preservación digital se ha convertido en una de les áreas de interés y en un reto para las instituciones que conservan pa-trimonio. En todo el mundo, las instituciones, a menudo de carácter nacional, han puesto en marcha iniciativas para hacerle frente y explorar soluciones. En nuestro país, la Biblioteca de Catalunya, en 2008, inició el diseño de un repositorio digital de preservación: COFRE (COnservamos para el Futuro Recursos Electrónicos), que desde 2010 se encuentra operativo. COFRE inicialmente fue impulsado para cubrir las necesidades propias de la Biblioteca, si bien siempre ha tenido la volun-tad y la visión de acoger a otras instituciones y ofrecer así un servicio de país. El artículo describe su origen, el contenido, los procesos, las características técnicas y la infraestructura

Acoplamiento del modelo regional de calidad de aire (CMAQ) con el modelo de emisiones locales mediante elementos finitos

Existen modelos regionales de calidad del aire que son muy utilizados. Estos modelos tienen modelos para estudiar el aporte de contaminantes provocados por fuentes importantes de contaminación, como pueden ser chimeneas, o poligonos industriales. El modelo regional que estudiamos en este trabajo es el CMAQ (Community Multiscale Air Quality), que usa el Plume-in-Grid (PinG) como modelo para estudiar el aporte de fuentes locales de contaminación. El PinG és un modelo lagrangiano de pluma gausiana, y en este trabajo queremos cambiar esta estratégia de modelación de emisores puntuales por un modelo euleriano por elementos finitos. Para poder conseguir la integración, mallamos nuestro volumen de estudio, mediante una estratégia que nos permite la fácil integración de los tetrahedros de nuestro modelo de elementos finitos, con los elementos del modelo regional. Tambien necesitamos interpolar el campo de viento que nos da el modelo regional para conocer el campo de viento los nodos de nuestro dominio. Finalmente necesitamos usar los valores de contaminación del modelo regional en nuestro modelo local

Machine learning requirements for energy-efficient virtual network embedding

Network virtualization is a technology proven to be a key enabling a family of strategies in different targets, such as energy efficiency, economic revenue, network usage, adaptability or failure protection. Network virtualization allows us to adapt the needs of a network to new circumstances, resulting in greater flexibility. The allocation decisions of the demands onto the physical network resources impact the costs and the benefits. Therefore it is one of the major current problems, called virtual network embedding (VNE). Many algorithms have been proposed recently in the literature to solve the VNE problem for different targets. Due to the current successful rise of artificial intelligence, it has been widely used recently to solve technological problems. In this context, this paper investigates the requirements and analyses the use of the Q-learning algorithm for energy-efficient VNE. The results achieved validate the strategy and show clear improvements in terms of cost/revenue and energy savings, compared to traditional algorithms.This work has been supported by the Agencia Estatal de Investigación of Ministerio de Ciencia e Innovación of Spain under project PID2019-108713RB-C51 MCIN/AEI/10.13039/501100011033.Peer ReviewedPostprint (published version

Insights into the Kinetics Degradation of Bisphenol A by Catalytic Wet Air Oxidation with Metals Supported onto Carbon Nanospheres

Emerging pollutants are an increasing problem in wastewater globally. Bisphenol A (BPA) is one compound belonging to this group. This work proposes the study of the employment of several metal-supported (2 wt. %) carbon nanospheres (CNS) for BPA degradation by catalytic wet-air oxidation. Several techniques were used for the catalyst characterization: thermogravimetry, X-ray diffractometry (XRD), Fourier transformed infrared spectrometry (FTIR), determination of isoelectric point, elemental analysis, X-ray fluorescence (XRF), scanning electron microscopy (SEM), and N2 adsorption–desorption isotherms. Different loads of Ru in the catalyst were also tested for BPA degradation (1, 2, 5, 7, and 10%), being the first minimum value to achieve a conversion above 97% in 90 min 2 wt. % of Ru in the CNS-Ru catalyst. In the stability test with CNS-Ru and CNS-Pt, CNS-Pt demonstrated less activity and stability. Two potential models were proposed to adjust experimental data with CNS-Ru(2%) at different conditions of BPA initial concentration, catalyst mass, temperature, and pressure of the reaction. Both models showed a high determination coefficient (R2 > 0.98). Finally, the efficiency of CNS-Ru and CNS-Pt was tested in a real hospital wastewater matrix obtaining better results the CNS-Pt(2%) catalyst.Depto. de Ingeniería Química y de MaterialesFac. de Ciencias QuímicasTRUEComunidad de Madridpu

Density, structure and dynamics of water: the effect of Van der Waals interactions

It is known that ab initio molecular dynamics (AIMD) simulations of liquid water, based on the generalized gradient approximation (GGA) to density functional theory (DFT), yield structural and diffusive properties in reasonable agreement with experiment only if artificially high temperatures are used in the simulations. The equilibrium density, at normal conditions, of DFT water has been recently shown by Schmidt et al. [J. Phys. chem. B, 113, 11959 (2009)] to be underestimated by different GGA functionals for exchange and correlation, and corrected by the addition of interatomic pair potentials to describe van derWaals (vdW) interactions. In this contribution we present a DFTAIMD study of liquid water using several GGA functionals as well as the van der Waals density functional (vdW-DF) of Dion et al. [Phys. Rev. Lett. 92, 246401(2004)]. As expected, we find that the density of water is grossly underestimated by GGA functionals. When a vdW-DF is used, the density improves drastically and the experimental diffusivity is reproduced without the need of thermal corrections. We analyze the origin of the density differences between all the functionals. We show that the vdW-DF increases the population of non-H-bonded interstitial sites, at distances between the first and second coordination shells. However, it excessively weakens the H-bond network, collapsing the second coordination shell. This structural problem is partially associated to the choice of GGA exchange in the vdW-DF. We show that a different choice for the exchange functional is enough to achieve an overall improvement both in structure and diffusivity.Comment: 11 pages, 9 figures, submitted. Revised versio