Sur le fil

Cet article interroge l’œuvre d’Annette Messager, une femme et artiste contemporaine qui aime les mots et le langage en général. Il s’agit d’analyser comment cette démarche artistique questionne l’image et le rôle des femmes dans notre société, et sa misogynie ordinaire. L’artiste joue avec les pratiques populaires, intimes et minoritaires. Aussi travaille-t-elle souvent avec du tissu pour ses propriétés matérielles et symboliques ou constitue-t-elle de petites collections. Elle cherche aussi son inspiration dans les œuvres du passé qui retentissent dans sa mémoire et propose souvent des installations pour faire participer le spectateur. Elle questionne enfin les rapports entre textes et images ou objets en privilégiant les séries et les variations. On a dit de ses œuvres que c’étaient des « bricoles »… Elle le revendique volontiers à présent !This article focuses on the works of the contemporary artist Annette Messager, who loves words and language in general. It analyzes how her artistic process questions the image of women and their role in our society, and its ordinary misogyny. The artist plays with popular, intimate, and minority practices. She thus often works with fabric because of its material and its symbolic properties, and she assembles small collections. Messager also seeks inspiration in the works of the past that resonate in her memory and she frequently proposes installations to engage the viewer. She also questions the relations between text and images or objects by emphasizing series and variations. Her works are often described as “des bricoles”. Today, she fully adheres to this description

MULTIPLE ORIFICE BUBBLE GENERATION IN GAS-SOLID FLUIDIZED BEDS: THE ACTIVATION REGION APPROACH

This work addresses the bubble generation mechanism at multi-orifice distributors in gas-solid fluidized beds (FB). Different measurements techniques such as high speed video camera and Kistler pressure transducers were applied to obtain information from both local, and global bed dynamics. Pressure fluctuation time series are used for dynamic diagnosis of the 2-D facility used during the study. The bed was operated with different distributor plates at several bubbling conditions leading to different bubble flow patterns characterized by digital image analysis of both the dense and the bubble phases. In order to explain the bubble pattern developed within the bed and the measured bubble dynamics, a phenomenological discrete bubble model is used. This model proposes an activation region (AR) mechanism for multi-orifice bubble generation. The underlying hypothesis is that the bubble formation can be placed in a region above the distributor plate where the initial bubble size is the result of the dynamical interaction of neighbour orifices. From the analysis of the experimental results, it is observed how for two different uniform gas distribution across the distributor plate, bubble dynamics interactions play the main role as the driver of the resulting bubble flow pattern developed within the bed. Moreover, when the activation region hypothesis is used as a bubble generation mechanism in a phenomenological discrete bubble model, it is seen that the proposed activation region mechanism, explains the observed bubble generation phenomena at multi-orifice distributors, and leads to a substantial decrease of the computational cost to simulate bubbling FB dynamics

Choosing IoT-connectivity? A guiding methodology based on functional characteristics and economic considerations

Along with the growing market of Internet of Things (IoT), the set of IoT-connectivity networks is also continuously expanding. Large-scale deployments of the new low-power wide-area networks and announcements of new technologies prove this trend. Although these new technologies take care of some key IoT-challenges, such as communication cost and power consumption, careful consideration of the IoT-connectivity is still required since there is no one-size-fits-all solution. Typical comparisons of IoT-connectivity networks are based on technical characteristics but remain unpractical when it comes down to comparing functional characteristics. Questions on public network accessibility, ability for private network deployments, and cost considerations related to IoT-connectivity networks often remain unanswered. In this work, a 2-step methodology is proposed to guide IoT-developers in choosing an appropriate connectivity network. First, a questionnaire walkthrough eliminates IoT-connectivity networks based on mismatches between their functional characteristics and the functional requirements of the IoT-applications. In a second step, an evaluation of the main cost components related to IoT-connectivity indicates the most economical solution. As an illustration, we present 2 case studies: (1) deploying smart shipping containers in the port of Antwerp and (2)installing shop'n go parking spaces, which detect vehicle presence via asensor

Empowering the Internet of Vehicles with Multi-RAT 5G Network Slicing

Internet of Vehicles (IoV) is a hot research niche exploiting the synergy between Cooperative Intelligent Transportation Systems (C-ITS) and the Internet of Things (IoT), which can greatly benefit of the upcoming development of 5G technologies. The variety of end-devices, applications, and Radio Access Technologies (RATs) in IoV calls for new networking schemes that assure the Quality of Service (QoS) demanded by the users. To this end, network slicing techniques enable traffic differentiation with the aim of ensuring flow isolation, resource assignment, and network scalability. This work fills the gap of 5G network slicing for IoV and validates it in a realistic vehicular scenario. It offers an accurate bandwidth control with a full flow-isolation, which is essential for vehicular critical systems. The development is based on a distributed Multi-Access Edge Computing (MEC) architecture, which provides flexibility for the dynamic placement of the Virtualized Network Functions (VNFs) in charge of managing network traffic. The solution is able to integrate heterogeneous radio technologies such as cellular networks and specific IoT communications with potential in the vehicular sector, creating isolated network slices without risking the Core Network (CN) scalability. The validation results demonstrate the framework capabilities of short and predictable slice-creation time, performance/QoS assurance and service scalability of up to one million connected devices.EC/H2020/825496/EU/5G for cooperative & connected automated MOBIility on X-border corridors/5G-MOBI

Experiences Developing Safe and Fault-Tolerant Tele-Operated Service Robots. A Case Study in Shipyards

Human operators use tele-operated service robots for performing more or less hazardous operations (manipulation of heavy and/or dangerous products) in more or less hostile environments (nuclear reactors, space missions, warehouses, etc). Anyway, independently of the operation, the robot has to interact with both the environment it is working on and with human operators. Therefore, it is essential that the design (which include both software and hardware) of the robot involves no risk, or at least an acceptable level of risk, neither for the operators, nor for the environment nor for the robot itself. Nevertheless, it is not always possible to make a system free of failures in its design or operation. Apart from the risk inherent to the use of the mechanisms themselves, these systems work in hazardous environments, where the probability of the risk is higher than normal. Should a failure happen, its consequences could even involve the loss of human lives. (Neumann, 1994) documents many cases of computer-related failures, such as the Therac-25 (a radiation-therapy device), the missiles shield in Saudi Arabia, etc. Nevertheless, safety aspects are seldom included in the early phases of the system design process from the beginning, even though they are a critic aspect. Generally, safety has to conform and adapt to the already designed system and not vice versa, when it is widely known that safety involves not only the design of the software but also the hardware. Even more, a simple hardware solution can eliminate a hazard or simplify the software design in many situations.This research has been funded by the Spanish CICYT project MEDWSA (TIN2006-15175- C05-02) and the Regional Government of Murcia Séneca Program (02998-PI-05)

SymbioCity: Smart Cities for Smarter Networks

The "Smart City" (SC) concept revolves around the idea of embodying cutting-edge ICT solutions in the very fabric of future cities, in order to offer new and better services to citizens while lowering the city management costs, both in monetary, social, and environmental terms. In this framework, communication technologies are perceived as subservient to the SC services, providing the means to collect and process the data needed to make the services function. In this paper, we propose a new vision in which technology and SC services are designed to take advantage of each other in a symbiotic manner. According to this new paradigm, which we call "SymbioCity", SC services can indeed be exploited to improve the performance of the same communication systems that provide them with data. Suggestive examples of this symbiotic ecosystem are discussed in the paper. The dissertation is then substantiated in a proof-of-concept case study, where we show how the traffic monitoring service provided by the London Smart City initiative can be used to predict the density of users in a certain zone and optimize the cellular service in that area.Comment: 14 pages, submitted for publication to ETT Transactions on Emerging Telecommunications Technologie

Implantación de plataforma virtual en prácticas docentes interuniversitarias en el Internet de las Cosas

Las titulaciones compartidas e impartidas por distintas instituciones universitarias están cobrando gran auge, ya que permiten aunar esfuerzos y ofrecer títulos interdisciplinares que aprovechan la sinergia entre profesorado diverso. No obstante, la descentralización de los estudiantes conlleva el reto de mantener la calidad y homogeneidad de la docencia en todas las instituciones implicadas, especialmente en las sesiones prácticas. Por este motivo, en este trabajo se propone una metodología docente en una asignatura de Internet de las Cosas en un máster interuniversitario impartido por dos centros españoles, que requiere tratar con grupos de estudiantes heterogéneos y material para prácticas distinto en ambas sedes. Se ha desarrollado un sistema de prácticas presenciales y virtuales que es común para el alumnado de ambas instituciones, de modo que ambos grupos realizan las mismas sesiones aun no disponiendo de un equipamiento de prácticas homogéneo. Las prácticas tienen un enfoque técnico, incluyendo el montaje y programación de circuitos electrónicos con Arduino y su interconexión con una plataforma de Internet de las Cosas en la nube. Mientras que los estudiantes presenciales tienen acceso a los componentes hardware del sistema a desplegar, los que asisten en remoto realizan el mismo montaje a través de una plataforma de simulación on-line, permitiendo desarrollos equivalentes y un seguimiento homogéneo en el ejercicio docente. La propuesta se encuentra actualmente en fase de ejecución y este trabajo presenta sus principales características, identificando los retos para los siguientes cursos académicos.The degrees shared by different universities are gaining momentum lately. They allow to combine efforts and offer interdisciplinary degrees to students, taking advantage of the synergy among diverse teaching staff. However, the decentralization of students brings the challenge of maintaining quality and homogeneity of education, especially in practical sessions. For this reason, this paper proposes a teaching methodology in a subject focused on the Internet of Things (IoT). This subject is framed in an interuniversity master taught by two Spanish centers, which requires dealing with heterogeneous students and equipment for practices in both venues. Therefore, a common laboratory program has been developed for the students of both institutions, so that both groups perform the same laboratory sessions even if they do not have a homogeneous equipment. The practices have an eminent technical approach, including the assembly and programming of electronic circuits with Arduino and its interconnection with an IoT platform in the cloud. While the face-to-face students have access to the real hardware components, those who attend remotely do the same work through an on-line simulation platform, allowing equivalent developments and a homogeneous follow-up of sessions. The proposed teaching methodology is currently in its execution phase and this paper presents its main features, identifying major challenges for the coming years.Este trabajo ha sido realizado con el soporte del proyecto PERSEIDES (TIN2017-86885-R) del Ministerio de Economía, Industria y Competitividad, del Programa Ramón y Cajal (RYC-2017-23823) del Misterio de Ciencia, Innovación y Universidades, así como del programa “Ayudas para la Excelencia de los Equipos de Investigación Avanzada en Ciberseguridad“ del INCIBE (INCIBEI-2015-27363)

New Mussel Inspired Polydopamine-Like Silica-Based Material for Dye Adsorption

A straightforward and economic procedure has been developed for the synthesis of a new polydopamine-like silica-based material that has been obtained by oxidation of catechol with KIO4 followed by reaction with 3-aminopropyltrimethoxysilane. All techniques adopted for characterization showed that the obtained material is rich in different functional groups and the morphological analyses revealed dimensions in the nanometric range. The hybrid material has been characterized by several techniques showing its polydopamine-like nature, and preliminary observations for dye adsorption have been reported.University of Palermo PRIN2017- 2017YJMPZ

Heteropolycompounds as catalysts for biomass product transformations

[EN] In the present review we show a variety of biomass product transformations through catalysis by both bulk and supported heteropolycompounds. The biomass sources considered include carbohydrates, oils and fats, and terpenes as main starting material groups. The products obtained and their applications are presented.We thank CONICET (PIP 003), Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina) (PICT 0406), and Universidad Nacional de La Plata for financial support. GPR and HJT are members of CONICET. MJC and SI thank to Spanish Government-MINECO through Consolider Ingenio 2010-Multicat project for financial support.Sanchez, LM.; Thomas, HJ.; Climent Olmedo, MJ.; Romanelli, GP.; Iborra Chornet, S. (2016). Heteropolycompounds as catalysts for biomass product transformations. Catalysis Reviews: Science and Engineering. 58(4):497-586. doi:10.1080/01614940.2016.1248721S49758658