Culture informationnelle et didactique de l'information. Synthèse des travaux du GRCDI, 2007-2010

GRCDI (Group of Researches in Culture and Didactic of Information) is a research group created in 2007 with the lead of the Urfist of Rennes. It has been institutionally attached to the ERTé «Culture informationnelle et curriculum documentaire » and is an extension proper to the western regions. This summary report was prepared in connection with the final report of the ERTé and is based on all publications of the group since 2007. His aim is to make an inventory of the group's conception of culture and information's didactics. It is structured around three main fields: the emergence, the approaches and the issues. The first part seeks to analyze and track the twin phenomena of emergence and development of culture of information and didactic of information. The second part attempts to account for the diversity and the multiplicity of approaches, concepts and aspects of the culture of information and information's didactics. At last, the third part deals with the issues under discussion, problems, obstacles and works in progress in both areas. A fourth field, focusing on the issue of Lis Curriculum, is examined through the recommendations of GRCDI. The aim is not here to provide a turnkey Lis curriculum but to prepare the ground for the development of a future curriculum with advices that illuminate the different aspects structuring the curriculum project.Le GRCDI (Groupe de Recherche sur la Culture et la Didactique de l'Information) est un groupe de recherche créé en 2007 à l'initiative de l'URFIST de Rennes et rattaché à l'ERTé «Culture informationnelle et curriculum documentaire », dont il constitue le prolongement pour les régions de l'Ouest. Ce rapport de synthèse, élaboré en lien avec le rapport final de l'ERTé, est fondé sur l'ensemble des publications du groupe depuis 2007 et vise à faire un état des lieux de la réflexion du groupe sur la culture informationnelle et la didactique de l'information. Il est structuré autour de trois grandes entrées : l'émergence, les approches, les questions. La première partie cherche à analyser et retracer le double phénomène d'émergence et de développement de la culture informationnelle et de la didactique info-documentaire. La deuxième partie tente de rendre compte de la diversité, de la multiplicité des approches, des conceptions et des facettes de la culture et de la didactique de l'information. Enfin la troisième partie porte sur les questions en débat, les problèmes, les obstacles, les chantiers ouverts dans chacun des deux domaines. A ces trois entrées transversales s'ajoute une quatrième, centrée sur la question du curriculum info-documentaire et faisant état des remarques et des préconisations du GRCDI. Il ne s'agit pas ici de fournir un curriculum info-documentaire, livré clés en mains et directement applicable, mais de préparer le terrain à l'élaboration du futur curriculum, en installant un balisage et en éclairant les différentes facettes structurant le projet curriculaire

Parameterized Hardware Design on Reconfigurable Computers: An Image Processing Case Study

Reconfigurable Computers (RCs) with hardware (FPGA) co-processors can achieve significant performance improvement compared with traditional microprocessor (μP)-based computers for many scientific applications. The potential amount of speedup depends on the intrinsic parallelism of the target application as well as the characteristics of the target platform. In this work, we use image processing applications as a case study to demonstrate how hardware designs are parameterized by the co-processor architecture, particularly the data I/O, i.e., the local memory of the FPGA device and the interconnect between the FPGA and the μP. The local memory has to be used by applications that access data randomly. A typical case belonging to this category is image registration. On the other hand, an application such as edge detection can directly read data through the interconnect in a sequential fashion. Two different algorithms of image registration, the exhaustive search algorithm and the Discrete Wavelet Transform (DWT)-based search algorithm, are implemented on hardware, i.e., Xilinx Vertex-IIPro 50 on the Cray XD1 reconfigurable computer. The performance improvements of hardware implementations are 10× and 2×, respectively. Regarding the category of applications that directly access the interconnect, the hardware implementation of Canny edge detection can achieve 544× speedup

Electronically Tuned Local Oscillators for the NOEMA Interferometer

We present an overview of the electronically tuned local oscillator (LO) system developed at the Institut de RadioAstronomie millimetrique (IRAM) for the superconductor-insulator-superconductor (SIS) receivers of the NOrthern Extended Millimeter Array interferometer (NOEMA). We modified the frequency bands and extended the bandwidths of the LO designs developed by the National Radio Astronomy Observatory (NRAO) for the Atacama Large Millimeter Array (ALMA) project to cover the four NOEMA LO frequency ranges 82-108.3 GHz (Band 1), 138.6-171.3 GHz (Band 2), 207.7-264.4 GHz (Band 3), and 283-365 GHz (Band 4). The NOEMA LO system employs commercially available MMICs and GaAs millimeter MMICs from NRAO which are micro-assembled into active multiplied chain (AMC) and power amplifier (PA) modules. We discuss the problem of the LO spurious harmonics and of the LO signal directly multiplied by the SIS mixers that add extra noise and lead to detections of unwanted spectral lines from higher order sidebands. A waveguide filter in the LO path is used to reduce the higher order harmonics level of the LO at the output of the final frequency multiplier, thus mitigating the undesired effects and improving the system noise temperature

Design of Active Waweguide OMT for Radio Astronomy Receiver Array in the 3 MM Band

We describe the design of an integrated cryogenic receiver module based on an “active” waveguide Orthomode Transducer (OMT) for dual-polarization radio astronomy observations across 75-116 GHz (3-mm band). The receiver module consists of passive and active sections that can be incorporated in a very compact mechanical assembly suitable for integration in a focal plane array. The passive section of the receiver module employs a broadband backward-coupler waveguide OMT while the active section consists of ultra-low noise MMIC (Monolithic Microwave Integrated Circuit) amplifiers

Design of Power Stage of INAF GAIA Board for biasing of AETHRA WP1 downconverter

The GAIA digital board developed by INAF was designed to bias up to ten stages of cryogenic low noise amplifiers (LNAs) and to deliver a maximum drain current Idmax50 mA with a drain voltage Vdmax5 V for each of them. The GAIA board monitors and controls each of the stages independently. However, such board cannot be employed to monitor and control the AETHRA WP1 75-116 GHz downconverter module as the power amplifiers of the fully-integrated MMIC developed at IAF, integrated into the downconverter module, require current values of up to 300 mA each, that is six times greater than what GAIA can deliver. Therefore, a power stage of the GAIA board has to be developed to comply with the high-current bias requirements of the AETHRA WP1 downconverter. Here, we describe the design of the power stage of the GAIA board, named PSG (Power Stage Gaia). The PSG is a four-layer digital bias board, to be connected in series with GAIA, capable of delivering up to 10 × high-current stages. One GAIA board is used to monitor and control one PSG board. The latter is an extension of GAIA and cannot be used independently of it. Therefore, one GAIA board plus one PSG board must be used in conjunction to monitor and control up to 10 high-current stages of the AETHRA WP1 downconverter. The version 1.2 of the GAIA board, developed for biasing, monitoring and controlling of the LNAs, cannot be used in conjunction with the PSG but requires a small modification to allow data interchange between the two boards. A new GAIA board, version 1.5, must be used in conjunction with the PSG

Culture informationnelle et didactique de l\u27information

Le GRCDI (Groupe de Recherche sur la Culture et la Didactique de l\u27Information) est un groupe de recherche créé en 2007 à l\u27initiative de l\u27URFIST de Rennes et rattaché à l\u27ERTé «Culture informationnelle et curriculum documentaire », dont il constitue le prolongement pour les régions de l\u27Ouest. Ce rapport de synthèse, élaboré en lien avec le rapport final de l\u27ERTé, est fondé sur l\u27ensemble des publications du groupe depuis 2007 et vise à faire un état des lieux de la réflexion du groupe sur la culture informationnelle et la didactique de l\u27information. Il est structuré autour de trois grandes entrées : l\u27émergence, les approches, les questions. La première partie cherche à analyser et retracer le double phénomène d\u27émergence et de développement de la culture informationnelle et de la didactique info-documentaire. La deuxième partie tente de rendre compte de la diversité, de la multiplicité des approches, des conceptions et des facettes de la culture et de la didactique de l\u27information. Enfin la troisième partie porte sur les questions en débat, les problèmes, les obstacles, les chantiers ouverts dans chacun des deux domaines. A ces trois entrées transversales s\u27ajoute une quatrième, centrée sur la question du curriculum info-documentaire et faisant état des remarques et des préconisations du GRCDI. Il ne s\u27agit pas ici de fournir un curriculum info-documentaire, livré clés en mains et directement applicable, mais de préparer le terrain à l\u27élaboration du futur curriculum, en installant un balisage et en éclairant les différentes facettes structurant le projet curriculaire

The Front-End of the NOEMA Interferometer

The IRAM Plateau de Bure Interferometer (PdBI) is being upgraded to a new powerful millimeter-wave radio astronomy facility called the NOrthern Extended Millimeter Array (NOEMA) which will double the number of the 15-m diameter antennas from six to 12. All antennas will be equipped with a new generation of dual-polarization Front-End covering the 72-373-GHz frequency range with four independent receivers integrated into a single cryostat. All receivers utilize sideband separating (2SB) superconductor-insulator-superconductor (SIS) mixers, each of which delivers two ~7.7-GHz-wide intermediate frequency (IF) outputs per polarization channel, thus increasing the total IF bandwidth which can be processed with a single setting of the interferometer from 8 GHz (2 × 4 GHz delivered by the existing PdBI Front-End) to ~31 GHz (4 × 7.7 GHz delivered by the NOEMA Front-End). The first of the new NOEMA antennas (Ant. 7) has recently been completed and the first NOEMA Front-End successfully developed and installed in it. For the coming years, our goal is to upgrade all of the Front-Ends currently installed on the six existing PdBI antennas to the new NOEMA standard and to build six additional ones (plus one spare) for the new NOEMA antennas. In this paper, we describe the design, fabrication, and assembly of the Front-End we have developed for NOEMA Antenna 7. The instrument has state-of-the-art performance and sets a new standard in the post-ALMA generation technology

Re‐evaluation of stannous chloride (E 512) as food additive

The Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion re‐evaluating the safety of stannous chloride and stannous chloride dihydrate (E 512) as food additives. The Panel considered that adequate exposure and toxicity data were available. Stannous chloride is only permitted as food additives in one food category and no reply on the actual use level of stannous chloride (E 512) as a food additive and on its concentration in food was provided by any interested party. According to the Mintel's Global New Products Database (GNPD), stannous chloride was not labelled on any products in the EU nor in Norway. The regulatory maximum level exposure assessment scenario is based on the maximum permitted levels (MPLs) for stannous chloride (E 512), which is 25 mg Sn/kg. The mean exposure to stannous chloride (E 512) from its use as a food additive was below 1.3 μg Sn/kg body weight (bw) per day for all age groups. The 95th percentile of exposure to stannous chloride (E 512) ranged from 0.0 μg Sn/kg bw per day in all groups to 11.2 μg Sn/kg bw per day in adults. Absorption of stannous chloride from the gastrointestinal tract is low there is no concern with respect to carcinogenicity and genotoxicity. Gastrointestinal irritation was reported in humans after ingestion of a bolus dose of 40 mg Sn. The Panel concluded that stannous chloride (E 512) is of no safety concern in this current authorised use and use levels

L'éducation à la culture informationnelle

La publication des actes du colloque international L'éducation à la culture informationnelle (Lille, octobre 2008 - sous le patronage de l'Unesco) présente les regards de chercheurs, de praticiens ou de représentants d'institutions sur cette notion et ouvre de larges perspectives interdisciplinaires. Le nouveau concept de « culture informationnelle » est proposé par la communauté internationale pour mieux appréhender la complexification actuelle des relations entre l'enseignement, l'éducation et l'information, liée au développement exponentiel des technologies numériques. Quel rapport entretient l'éducation à l'information (information literacy) avec l'éducation aux médias (media literacy) et l'éducation numérique (digital literacy) ? Le périmètre de la « culture informationnelle » s'étend maintenant clairement au-delà du monde de la documentation et des bibliothèques. La notion même doit être précisée, revue, alors que les pratiques continuent d'évoluer. Une place importante est consacrée dans l'ouvrage à l'analyse comparée des approches théoriques et de plusieurs expériences menées dans différents pays