Search

International audience; Ultrasonic welding is a serious candidate in the development of methods to assemble papers and paperboards without using additional substances. However, the ultrasonic welding of papers remains a technological challenge considering the low weldability of lignocellulosic materials. This study aims to investigate on the ultrasonic welding process applied to papers in order to identify the processing conditions which favor the formation of strong welded joints. To reach such purpose, an experimental strategy was developed by combining the characterization of welded materials and the monitoring of process parameters. Experimentations were performed using a reference paper displaying a good weldability to specifically highlight the contribution of process parameters. Results indicate that the process is highly sensitive to vibration amplitude, power supplied by the high frequency generator, and sample thickness. Power seems to be a reliable indicator of the severity of the process. A strong decrease in the strength of the welded joints is observed when working with low thicknesses. It seems that the layers coated on top of papers are the main part of the material contributing in the development of adhesion at the welding joint. Overall, instrumenting the device has led to a better understanding of the ultrasonic welding of papers.

International audience; This paper focuses on the problem of the hierarchical multi‐label classification of research papers, which is the task of assigning the set of relevant labels for a paper from a hierarchy, using reduced amounts of labelled training data. Specifically, we study leveraging unlabelled data, which are usually plentiful and easy to collect, in addition to the few available labelled ones in a semi‐supervised learning framework for achieving better performance results. Thus, in this paper, we propose a semi‐supervised approach for the hierarchical multi‐label classification task of research papers based on the well‐known Co‐training algorithm, which exploit content and bibliographic coupling information as two distinct papers' views. In our approach, two hierarchical multi‐label classifiers, are learnt on different views of the labelled data, and iteratively select their most confident unlabelled samples, which are further added to the labelled set. The success of our suggested Co‐training‐based approach lies in two main components. The first is the use of two suggested selection criteria (i.e., Maximum Agreement and Labels Cardinality Consistency) that enforce selecting confident unlabelled samples. The second is the appliance of an oversampling method that rebalances the labels distribution of the initial labelled set, which reduces the reinforcement of the label imbalance issue during the Co‐training learning. The proposed approach is evaluated using a collection of scientific papers extracted from the ACM digital library. Performed experiments show the effectiveness of our approach with regards to several baseline methods.

International audience; The origin of Tibetan papermaking is poorly documented. Up to now, only the Tibetan paper fragments from Endere and Dunhuang sites have been scientifically studied outlining the basic knowledge about plant fiber uses and artwork manufacturing procedures. In order to deepen the knowledge on the unique ancient Tibetan papermaking, we report here the analysis of a set of paper fragments from the Samye Monastery in south Tibet, China. Multidisciplinary scientific investigations utilizing 14C radiocarbon dating, microscopic observation, scanning electron microscopy (SEM), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), pyrolysis-comprehensive gas chromatography/mass spectrometry (Py-GCxGC/MS), and proteomic analysis have been applied to these ancient paper fragments. The results show that the fragments were dated to the 12th~13th century AD and made from fibers of the Thymelaeaceae family plant Stellera Chamaejasme L of which the fiber’s chemical profiles have been firstly studied. The presence of starch granules from Triticum spp wheat and proteins from bovine milk (more likely assigned to native yak), offers the first indication that a unique sizing technique using starch-milk sizing had been employed in early Tibetan papermaking, compared to using alum-animal glue sizing agent which is more popular in contemporary Central China. The combined use of organic material (unaltered starch grains) and inorganic material (calcium carbonate) as paper fillers is also firstly revealed in Tibetan papermaking. The application of Py-GC/MS, Py-GCxGC/MS and proteomic analysis revealed more detailed profiles of early Tibetan hand papermaking, indicating that these methods have great potential to explore the production technology of ancient handmade papers.

International audience; The durability of paper documents treated with aminoalkylalkoxysilane copolymer (co-AAAS) flexible networks, as deacidifying and strengthenening agents, was studied. To this end, a 1922 lignocellulos ic newsprint paper was treated with co-AAASs and characterized. Physico-chemical properties such as pH, chromatism, opacity and mechanical strength were measured shortly upon treatment and several years after. In order to better understand the role of the initial degradation state of the paper and the impact of its constituents other than cellulose (lignin, alum-rosin sizing) on the treatment efficiency, several laboratory papers were added as models. It was shown that alum-rosin sizing contributed to a decrease in pH of the most degraded treated paper over the monitoring time, whereas the strengthening effect was mostly affected by the presence of lignin. In particular, for most papers, after several years, the gain in folding endurance was the lowest in the lignin-rich ones. The breaking length of all the papers increased post-treatment and over time, independently of the paper constituents. This was attributed to the slowly progressing aminoalkylalkoxysilanes polycondensation, on the scale of years, as evidenced by Cross Polarisation-Mass Angle Spinning 29 Si solid-state Nuclear Magnetic Resonance.

In this work, we describe an eco-friendly and cost-efficient method for the production of highly dispersed few-layer graphene solution using karaya gum as bio-inspired exfoliating agent. The as-synthesized graphene aqueous solution can be easily applied on paper sheet through dip- or brush-coating thanks to the binding properties of the gum and to the functional groups on the paper surface with the graphene sheets. The as-synthesized composites display high mechanical strength and high electrical conductivity for numerous downstream applications. Electronic circuits can be designed on such graphene-paper composites either by controlling the graphene deposit or by post-laser etching with high lateral resolution. The laser beam can also be used to create local graphitization or partial etching of the conductive line in order to generate conductive areas with different resistance. The designed smart graphene paper was experimentally tested in different electronic applications, such as lightweight conductive circuit, as well as flexible keyboard which can be directly linked to a computer, thus opening up a new route for the development of daily life connected objects.

International audience; The hemp plant Cannabis sativa Linn, referring to industrial hemp, is a high-yielding annual industrial crop grown providing fibers from hemp stalk and oil from hemp seeds. Although hemp is a niche crop, hemp production is currently undergoing a renaissance. More than 30 countries grow hemp, with China being the largest hemp producing and exporting country. Europe and Canada are also important actors in the global hemp market. Traditionally, hemp as a fiber plant has been used for the production of apparels, fabrics, papers, cordages and building materials. The hurds, as waste by-product of fiber production, were used for bedding of animals, the seeds for human nutrition, e.g., as flour, and the oil for a wide range of purposes, from cooking to cosmetics. Hemp has also been an important crop throughout human history for medicine. Other more recent applications include materials for insulation and furniture, automotive composites for interior applications and motor vehicle parts, bioplastics, jewelry and fashion sectors, animal feed, animal bedding, and energy and fuel production. Foods containing hemp seed and oil are currently marketed worldwide for both animal and human nutrition. They also find applications in beverages and in neutraceutical products. Hemp oil is also used for cosmetics and personal care items, paints, printing inks, detergents and solvents. It is estimated that the global market for hemp consists of more than 25,000 products. Currently, the construction and insulation sector, paper and textile industries, and food and nutrition domains are the main markets while the cosmetics and automotive sector are growing markets. Innovative applications, e.g., in the medical and therapeutic domains, cosmeceuticals, phytoremediation, acoustic domain, wastewater treatment, biofuels, biopesticides and biotechnology, open new challenges. Hemp is also the object of numerous fundamental studies. This review presents and discusses the traditional and new uses of industrial hemp.

Generated in the pulp and paper production process, cellulosic pulp fines are fibrous cellulosic materials capable of passing a 200 mesh screen. Processed pulp fines remain in the pulp and affect pulp and paper sheet properties. Their specific morphology promotes interactions with fibers and alters sheet properties. Nevertheless, the 3D distribution of fines in paper sheets has not been revealed so far. Localizing fines within a matrix of fibers is challenging since both elements have the same chemical composition and fines have small dimensions. It is required to increase the contrast of pulp fines, while avoiding any alteration of initial fines morphology. In this study, fines were first separated and labeled with Rhodamine B isothiocyanate, a fluorescent dye. Labeled fines were blended with pulp at different concentrations and paper sheets were produced from each mixture. Prior to imaging, pulps and handsheets were characterized by standard pulp and paper tests and compared with references, showing no significant differences between sheets containing labeled and untreated fines. Thus, mechanical and physical tests indicated that no, or only minor alteration of fines properties by the labeling process occurred. We then applied two imaging techniques to detect the labeled pulp fines in the paper network, namely confocal laser scanning microscopy and multiphoton microscopy, visualizing the 3D distribution of fluorescent fines within the fiber network. The results obtained also allowed a differentiation between morphologically different fines showing fiber fragments more attached to single fibers whereas more fibrillar fines concentrate in fiber–fiber joints, thereby strengthening bonding.

In order to make 2nd-generation biofuels more competitive, high solid-matter content has to be reached. To progress towards this target, the mechanism for destructuring lignocellulose fibres in semidilute conditions has to be well understood, as this configuration shows the basic mechanism which limits transfers and efficiency. This study aims to delve deeply into the biophysical and transfer limitations occurring during enzymatic hydrolysis. A specific experimental set-up associating in-situ and ex-situ physical (rheometry, chord length analysis) and biochemical analysis was used to expand the knowledge of hydrolysis of extruded softwood paper pulp over 24 h under different substrate concentrations (1%–3%) and enzyme doses (Accellerase 1500, 5 and 25 FPU/g cellulose). Non-Newtonian behaviour associated with pronounced yield stress stand as the major factors limiting process efficiency. A critical time was deduced from viscosity evolution, and the existence of a unique, dimensionless viscosity-time curve was established, suggesting similar mechanisms for fibre degradation. In addition, chord length distribution allowed for the description of population evolution and was discussed in the light of in-situ viscosity and hydrolysis yield. Physical (viscosity, particle size) and biochemical (substrate) kinetics were modelled (second-order) and coefficients identified. A chronology of the encountered phenomenological limitations demonstrates the necessity of optimising bioprocesses by considering physical parameters. A reference feed rate is proposed in order to reach high solid loading under fed-batch strategy.

cited By 0; In this work, we design new plasmonic paper-based nanoplatforms with interesting capabilities in terms of sensitivity, efficiency, and reproducibility for promoting multimodal biodetection via Localized Surface Plasmon Resonance (LSPR), Surface Enhanced Raman Spectroscopy (SERS), and Metal Enhanced Fluorescence (MEF). To succeed, we exploit the unique optical properties of gold nanobipyramids (AuBPs) deposited onto the cellulose fibers via plasmonic calligraphy using a commercial pen. The first step of the biosensing protocol was to precisely graft the previously chemically-formed p-aminothiophenol@Biotin system, as active recognition element for target streptavidin detection, onto the plasmonic nanoplatform. The specific capture of the target protein was successfully demonstrated using three complementary sensing techniques. As a result, while the LSPR based sensing capabilities of the nanoplatform were proved by successive 13-18 nm red shifts of the longitudinal LSPR associated with the change of the surface RI after each step. By employing the ultrasensitive SERS technique, we were able to indirectly confirm the molecular identification of the biotin-streptavidin interaction due to the protein fingerprint bands assigned to amide I, amide III, and Trp vibrations. Additionally, the formed biotin-streptavidin complex acted as a spacer to ensure an optimal distance between the AuBP surface and the Alexa 680 fluorophore for achieving a 2-fold fluorescence emission enhancement of streptavidin@Alexa 680 on the biotinylated nanoplatform compared to the same complex on bare paper (near the plasmonic lines), implementing thus a novel MEF sensing nanoplatform. Finally, by integrating multiple LSPR, SERS, and MEF nanosensors with multiplex capability into a single flexible and portable plasmonic nanoplatform, we could overcome important limits in the field of portable point-of-care diagnostics. © 2019 Campu, Susu, Orzan, Maniu, Craciun, Vulpoi, Roiban, Focsan and Astilean.

This work develops a multi-objective linear programming model for a multi-echelon, multi-product, multi-period supply chain planning. This model considers all dimensions of sustainable development paradigm simultaneously and expands six objective functions for making the model realistic. To solve this model and large-scale sustainable supply chain management, an improved version of the augmented e-constraint method (AUGMECON2) is used. Computational results illustrate the proposed model admitted various progresses in all the three pillars of sustainable development; namely remarkable progress, mildly progress and irregular one, respectively. In addition, important managerial insights are provided. Trade-off interactions between multi-objectives are perceived by the obtained Pareto solutions that represents the cost of being sustainable from the point of optimizing the social factors and environmental impacts. An application to the paper industry is presented and discussed.

Cellulose is an attractive reagent for the elaboration of C-containing materials, but here, we also considered it as an O-provider for preparing macro, micro and nano-fibrous Nb2O5/C composites by a new mineralization with Nb2Cl10 in anhydrous conditions. Our study highlights differences of reactivity between filter paper, microfibrillated or bacterial cellulose in connection with the crystallinity and the accessibility of the hydroxyl groups. The Nb2O5/C ratio was found to be adjustable (55?75% of Nb oxide) depending on the cellulosic precursor. Our composites were tested as electrodes that could be used as negative electrode in hybrid lithium-capacitor. Electrochemical characterizations of Nb2O5/C composites are reported and it was demonstrated that characteristics of the starting cellulosic reagents that influence physico-chemical properties of composites thus impact electrodes performances. Very interestingly, for 1C charging/discharging rates, capacities as good as thus of literature (150 mAh g−1) were obtained using our new sustainable synthesis protocol. Fil: Henry, Aurélien. Université Montpellier II; Francia Fil: Le Vot, Steven. Université Montpellier II; Francia Fil: Alauzun, Johan G.. Université Montpellier II; Francia Fil: Hesemann, Peter. Université Montpellier II; Francia Fil: Foresti, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina Fil: Cerruti, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina Fil: Heux, Laurent. Université Montpellier II; Francia Fil: Fontaine, Olivier. Université Montpellier II; Francia Fil: Boury, Bruno. Université Montpellier II; Francia

International audience; We study the mechanical response, and tearing features of crêpe paper, a two-dimensional, very anisotropic material, with one direction much less stiff than the other one. Depending on how the soft direction has been pre-stretched or not, the apparent Young modulus of the material can be varied over a broad range, while its fracture energy remains unaltered. The classical tearing concertina problem shows that a macroscopic measurement (the shape of the teared region) provides a direct access to the fracture properties of the material (effective Young's modulus, and fracture energy). The overall discussion is conducted in the frame of Griffith's theory of fracture.

International audience; To reduce pollution emissions and achieve a cleaner production in paper industry, it is essential to understand the inner links between concentrations of gaseous pollutants, types of final products and production techniques. In this study, the concentrations of four potential gaseous pollutants, total volatile organic compounds (TVOC), formaldehyde (HCHO), hydrogen sulfide (H 2 S), and hydrocarbon compounds (C x H y), in the ambient air on thirty sampling points of five pulp and paper mills were detected and analyzed. The results were summarized with respect to the following aspects: (1) Levels of four gaseous pollutants on all the sampling points in five mills. It was obvious that the situation of gaseous pollution from pulp mill was much more serious than those from paper mills. (2) Gaseous pollutant distinctions due to different production processes. The levels of gaseous pollutants from five mills were greatly influenced by the utilized raw materials and the applied paper chemical agents (flavor, coating materials and additives) in mills. (3) Gaseous pollution comparisons at common points. At the two common points in five mills, i.e. the wet end of paper machine and the wastewater treatment process, TVOC and HCHO, C x H y and H 2 S were the main gaseous pollutants, respectively. In addition, some feasible measures to realize a cleaner production in pulping and papermaking process were also put forward in the article.

International audience; Advanced internet and multimedia set-top boxes are today massively based on 4*4 MIMO systems, with multi-sub-bands standards (Wifi bands, LTE, Bluetooth,…). Multiple antennas spatially distributed on the plastic casing become therefore a great challenge for cost and performances motivations, thus promoting flexible technology and substrate, for assembling subsystems , under compactness considerations, as well as electrical performances improvement. In this paper, we discuss about the characterisation of Multi-band antennas designed on an ultra-low cost material (a cellulosic substrate, i.e. a paper) with design challenges in terms of radiation efficiency maximization and wideband properties under compactness constraints. Simulation and measurements are proposed to validate the designs.

Fibrous cellulosic materials have been used as templates for material synthesis or organization via thermal degradation of the cellulose. Most of these methods, however, fail to exploit fiber organization, in part due to loss of structure with processing. Herein, we demonstrate that chemi- and physi-sorbed modifiers of cellulose alters the thermal degradation mechanism allowing for controlled deposition of oxide and carbon (incomplete combustion) along the original paper fiber network. We demonstrate that the degradation of the cellulose fibers depends on the amount of physisorbed material due, in part, to effect on the propagation of the ignition event. From the distribution of the residual elements and shape of the deposits, we can infer that the thermal degradation process depends on the nature, and concentration, of filler(s) or occluded.

Fine prediction of the elastic properties of paper materials can now be obtained using sophisticated fibre scale numerical approaches. However, there is still a need, in particular for low-density papers, for simple and compact analytical models that enable the elastic properties of these papers to be estimated from the knowledge of various structural information about their fibres and their fibrous networks. For that purpose, we pursued the analysis carried out in Marulier et al. (Cellulose 22:1517–1539, 2015. https://doi.org/10.1007/s10570-015-0610-6 ) with low-density papers that were fabricated with planar random and orientated fibrous microstructures and different fibre contents. The fibrous microstructures of these papers were imaged using X-ray synchrotron microtomography. The corresponding 3D images revealed highly connected fibrous networks with small fibre bond areas. Furthermore, the evolutions of their Young’s moduli were non-linear and evolved as power-laws with the fibre content. Current analytical models of the literature do not capture these trends. In light of these experimental data, we developed a fibre network model for the in-plane elasticity of papers in which the main deformation mechanisms of the micromechanical model is the shear of the numerous fibre bonds and their vicinity, whereas the fibre parts far from these zones were considered as rigid bodies. The stiffness tensor of papers was then estimated both numerically using a discrete element code and analytically using additional assumptions. Both approaches nicely fit the experimental trends by adjusting a unique unknown micromechanical parameter, which is the shear stiffness of bonding zones. The estimate of this parameter is relevant in light of several recently reported experimental results.

International audience; We clarify some analytical expressions existing in the literature, • Within the correct formulae we conclude that there is no need for an ad hoc improvement on the opposite to the title paper, • We highlight the symmetry properties of the function to be integrated in order to agree with the usual assumptions made to derive the Kramers-Kronig relations, • The analytical formula we provide may be used to increase the accuracy of the "Poor Man's Kramers-Kronig analysis" method and the "Kramers-Kronig constrained variational analysis" method.

International audience; Among the programming models for parallel and distributed computing, one can identify two important families. The programming models adapted to data-parallelism, where a set of coordinated processes perform a computation by splitting the input data; and coordination languages able to express complex coordination patterns and rich interactions between processing entities. This article takes two successful programming models belonging to the two categories and puts them together into an effective programming model. More precisely, we investigate the use of active objects to coordinate BSP processes. We choose two paradigms that both enforce the absence of data-races, one of the major sources of error in parallel programming. This article explains why we believe such a model is interesting and provides a formal semantics integrating the notions of the two programming paradigms in a coherent and effective manner.

In this paper, we report the first successful implementation of a complete paper-based water management system (WMS) that collects the excess water at the cathode of a microfabricated packageless fuel cell (PLFC) and redistribute it to its anode and to an evaporation surface that simulate a hydride-based hydrogen generator. Five configurations of WMS were tested on a 1 cm2 air-breathing PLFC and show that with the best configuration, the power output of the cell can be improved by 90% for at least 24h. We experimentally demonstrate that not only cathode flooding issues must be address to obtain an efficient WMS but also that anode drying plays a major role in poor performance of small air-breathing fuel cells. Finally, with the optimal configuration of WMS, the PLFC in air-breathing mode shows similar performances as with humidity controlled air forced-flow.

International audience; The diagnosis of infectious diseases is entering a new and interesting phase. Technologies based on paper microfluidics, coupled to developments in isothermal amplification of Nucleic Acids (NAs) raise opportunities for bringing the methods of molecular biology in the field, in a low setting environment. A lot of work has been performed in the domain over the last few years and the landscape of contributions is rich and diverse. Most often, the level of sample preparation differs, along with the sample nature, the amplification and detection methods, and the design of the device, among other features. In this review, we attempt to offer a structured description of the state of the art. The domain is not mature and there exist bottlenecks that hamper the realization of Nucleic Acid Amplification Tests (NAATs) complying with the constraints of the field in low and middle income countries. In this domain however, the pace of progress is impressively fast. This review is written for a broad Lab on a Chip audience.

International audience; IntroductionIn January 2015, Rouen University Hospital’s information system experienced serious issues. It was necessary to rapidly switch from the computerized provider order entry (CPOE) system towards a paper-based order entry (PBOE) system. This was an opportunity to evaluate prescriber opinion on the two provider order entry (POE) systems.MethodsAll residents were asked to fill an augmented version of the POE satisfaction and usage survey for both POE systems. The results were compared to identify the strengths and weaknesses of each system.ResultsFifty-one respondents had used the CPOE system and the PBOE system. Overall, satisfaction was higher with PBOE than CPOE (odds ratio (OR) = 3.74; p < 0.001). Usability (OR = 4.00; p < 0.001), reliability (OR = 8.54; p < 0.001), time consumption (OR = 0.50; p < 0.05 – survey statement was formulated negatively), and communication with nurses (OR = 14.27; p < 0.0001) reached statistically better agreement. The more experience with CPOE the more residents were disillusioned with the reliability (OR = 6.55; p < 0.01), the usability (OR = 5.68; p < 0.01) and the patient safety (OR = 0.27; p < 0.05 – survey statement was formulated negatively) of CPOE. Although safety issues were reported for both systems, the causes were different; PBOE imposed frequent rewriting of the order while CPOE lack of usability might be unsafe. Another important issue with both POE systems was time consumption.ConclusionResidents did not report any increase in safety issues with the rapid switch from CPOE to PBOE. They even seemed more satisfied with the rollback to paper, which remains a possible degraded mode in case of health information technology collapse.

International audience; Whenever a bug or vulnerability is detected in the Linux kernel, the kernel developers will endeavour to fix it by introducing a patch into the mainline version of the Linux kernel source tree. However, many users run older "stable" versions of Linux, meaning that the patch should also be "backported" to one or more of these older kernel versions. This process is error-prone and there is usually a long delay in publishing the backported patch. Based on an empirical study, we show that around 8% of all commits submitted to Linux mainline are backported to older versions, but often more than one month elapses before the backport is available. Hence, we propose a patch backporting technique that can automatically transfer patches from the mainline version of Linux into older stable versions. Our approach first synthesizes a partial transformation rule based on a Linux mainline patch. This rule can then be generalized by analysing the alignment between the mainline and target versions. The generalized rule is then applied to the target version to produce a backported patch. We have implemented our transformation technique in a tool called FixMorph and evaluated it on 350 Linux mainline patches. FixMorph correctly backports 75.1% of them. Compared to existing techniques, FixMorph improves both the precision and recall in backporting patches. Apart from automation of software maintenance tasks, patch backporting helps in reducing the exposure to known security vulnerabilities in stable versions of the Linux kernel.

International audience; Cellulose paper degradation products forming in the “tideline” area at the wet-dry interface of pure cellulose paper were analyzed using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) and high-resolution electrospray ionization-mass spectrometry (ESI-MS, LTQ Orbitrap) techniques. Different extraction protocols were employed in order to solubilize the products of oxidative cellulose decomposition, i.e., a direct solvent extraction or a more laborious chromophore release and identification (CRI) technique aiming to reveal products responsible for paper discoloration in the tideline area. Several groups of low molecular weight compounds were identified, suggesting a complex pathway of cellulose decomposition in the tidelines formed at the cellulose-water-oxygen interface. Our findings, namely the appearance of a wide range of linear saturated carboxylic acids (from formic to nonanoic), support the oxidative autocatalytic mechanism of decomposition. In addition, the identification of several furanic compounds (which can be, in part, responsible for paper discoloration) plus anhydro carbohydrate derivatives sheds more light on the pathways of cellulose decomposition. Most notably, the mechanisms of tideline formation in the presence of molecular oxygen appear surprisingly similar to pathways of pyrolytic cellulose degradation. More complex chromophore compounds were not detected in this study, thereby revealing a difference between this short-term tideline experiment and longer-term cellulose aging.

International audience; The task of tagging papers with semantic metadata in order to analyze their relatedness represents a good foundation for a paper recommender system. The analysis from this paper extends from previous research in order to create a graph of papers from a specific domain with the purpose of determining each article's importance within the considered corpus of papers. Moreover, as non-latent representations are powerful when used in conjunction with latent ones, our system retrieves semantically close words, not present in the paper, in order to improve the retrieval of papers. Our previous analyses used the semantic representation of papers in different semantic models with the purpose of creating visual graphs based on the semantic relatedness links between the abstracts. The current analysis takes a step forward by proposing a model that can suggest which papers are of the highest relevance, share similar concepts, and are semantically related with the initial query. Our study is performed using paper abstracts in the field of information technology extracted from the Web of Science citation index. The research includes a use case and its corresponding results by using interactive and exploratory network graph representations.

Proof assistants are getting more widespread use in research and industry to provide certified and independently checkable guarantees about theories, designs, systems and implementations. However, proof assistant implementations themselves are seldom verified, although they take a major share of the trusted code base in any such certification effort. In this area, proof assistants based on Higher-Order Logic enjoy stronger guarantees, as self-certified implementations have been available for some years. One cause of this difference is the inherent complexity of dependent type theories together with their extensions with inductive types, universe polymorphism and complex sort systems, and the gap between theory on paper and practical implementations in efficient programming languages. MetaCoq is a collaborative project that aims to tackle these difficulties to provide the first fully-certified realistic implementation of a type checker for the full calculus underlying the Coq proof assistant. To achieve this, we refined the sometimes blurry, if not incorrect, specification and implementation of the system. We show how theoretical tools from this community such as bidirectional type-checking, Tait-Martin-L\"of/Takahashi's confluence proof technique and monadic and dependently-typed programming can help construct the following artefacts: a specification of Coq's syntax and type theory, the Polymorphic Cumulative Calculus of (Co)-Inductive Constructions (PCUIC); a monad for the manipulation of raw syntax and interaction with the Coq system; a verification of PCUIC's metatheory, whose main results are the confluence of reduction, type preservation and principality of typing; a realistic, correct and complete type-checker for PCUIC; a sound type and proof erasure procedure from PCUIC to untyped lambda-calculus, i.e., the core of the extraction mechanism of Coq., Comment: In Proceedings LFMTP 2021, arXiv:2107.07376

The use of cyclopropenone derivatives as latent photo-released strained cyclic alkynes is reported for the covalent printing of complex patterns on cellulose paper. Two different approaches using either a UV LED or a laser as light irradiation source are discussed. While the high intensity of the laser damages the grafted molecular layer, the use of a simple UV LED allows the printing in only 8 min at room temperature with a good resolution at the micrometer scale with negligible diffusion. The validity of this strategy is demonstrated through the sequential printing of a QR code and a logo on the same paper sheet.

International audience; This paper presents the design, implementation, and prototype of a low-cost Braille embossing mechanism. The proposal is a printer head integrating three hammers that, upon actuation, stamp readable dots on the paper. Inspired in the rotary cam-follower mechanism, the hammers are actuated by a single servomotor which rotation determines which hammer strikes the paper. Braille characters can be quickly embossed using the proposed printer head. Affordable and efficient Braille embossers for home use can be envisaged using this new action approach.

International audience

A review of the most important findings for jets impingement on rotating target is presented, the focus is on the heat transfer and flow dynamics in these jets. These jet configurations are encountered in many industrial applications. A significant number of research studies dealing with computational and experimental studies are reviewed. Different parameters are found to influence the flow and enhance mass and energy transfer in several heat configurations such as; Reynolds number (Re), nozzle geometry, spacing between jet exit and the impinging plate, jet impinging angle and the flow regime at the jet exit. There are a few studies that deal with heat transfer of a flow impinging on a rotating disk due to complexity of the flow structure and the challenges to conduct in-depth experimental investigation. Most studies present profiles of heat transfer coefficients, mean velocity and turbulence rates of the impinging flow. Many researches have reported that the LES can predict heat transfer and flow field data for different impinging angles to study the feedback mechanism between the nozzle and the plate.

International audience; We tested the performance of pyrolysis-comprehensive two-dimensional gas chromatography/massspectrometry in the course of our cultural heritage studies, and compared its potentialities for the char-acterization of traditional East Asian handmade papers with those previously obtained by pyrolysis-gaschromatography/mass spectrometry. The evaluation of the two methods was conducted in consider-ing the number of detected peaks, the compounds separation, the sensitivity, and the identificationof marker compounds. The results showed that the number of plant markers (triterpenes and phytos-terols) detected in a Japanese kozo reference paper was improved in the pyrolysis fingerprint. With again in sensitivity in the order of six, the case study of a museum sample confirmed that pyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry is more efficient for a reliableidentification of museum collections samples and/or archaeological samples where tiny quantities ofmaterials are the rule. The present study has been successful in refining a micro-destructive methodbased on analytical pyrolysis for the characterization of traditional East Asian handmade papers usingpyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry.

International audience; With the increasing development of handheld devices, Location Based Services (LBSs) became very popular in facilitating users' daily life with a broad range of applications (e.g. traffic monitoring, geo-located search, geo-gaming). However , several studies have shown that the collected mobility data may reveal sensitive information about end-users such as their home and workplaces, their gender, political, religious or sexual preferences. To overcome these threats, many Location Privacy Protection Mechanisms (LPPMs) were proposed in the literature. While the existing LPPMs try to protect most of the users in mobility datasets, there is usually a subset of users who are not protected by any of the existing LPPMs. By analogy to medical research, there are orphan diseases, for which the medical community is still looking for a remedy. In this paper, we present MooD, a fine-grained multi-LPPM user-centric solution whose main objective is to find a treatment to mobile users' orphan disease by protecting them from re-identification attacks. Our experiments are conducted on four real world datasets. The results show that MooD outperforms its competitors, and the amount of user mobility data it is able to protect is in the range between 97.5% to 100% on the various datasets. CCS Concepts • Security and privacy → Pseudonymity, anonymity and untraceability.

The influence of pressure on the optical properties of nanostructured tetragonal Cu2Sb has been investigated jointly by experimental Raman spectroscopy (RS) and theoretical first-principles calculation based on density functional theory (DFT) varying pressure from zero (ambient condition) to 45 GPa. The DFT determined pressure dependence of the Raman active modes and the mode-Gruneisen parameters for each Raman mode are found to be in excellent agreement with those experimentally determined. Comparison of the pressure evolution of the experimental Raman data with those of DFT has allowed us to make the proper assignment of optical phonon modes.

In 2018, the 40th IABSE Symposium was hosted in Nantes, France, with the main theme of “Tomorrow’s Megastructures”. The symposium was a great opportunity to debate the existing solutions, to develo...

International audience; We present a phenomenological model for the real-time simulation of paper tearing and sound. The model uses as input rotations of the hand along with the index and thumb of left and right hands to drive the position and orientation of two regions of a sheet of paper. The motion of the hands produces a cone shaped deformation of the paper and guides the formation and growth of the tear. We create a model for the direction of the tear based on empirical observation, and add detail to the tear with a directed noise model. Furthermore, we present a procedural sound synthesis method to produce tearing sounds during interaction. We show a variety of paper tearing examples and discuss applications and limitations.

International audience; Illustrators are advanced users of both traditional and computer-assisted drawing tools, and therefore, observing their strategies is very valuable for research on drawing interfaces. We interviewed four professional illustrators in their work environment. We also followed the work of an artist for a two-year period. We observed that artists mix a variety of techniques that involve specialized computer software and hardware such as Adobe Photoshop, a graphics tablet and a scanner, and traditional physical tools such as pencils, paper, and customized light tables. Our findings inspired BricoSketch, an augmented paper interface that enables illustrators to zoom into parts of their drawings and work at different levels of detail on paper. Our early results demonstrate that BricoSketch supports real tasks, improving productivity on paper while enhancing illustrators’ creative ways of working.

International audience; Iron gall inks have largely been used for writing in European western countries from the Middle Ages to the twentieth century. Yet, their use may significantly damage the paper through acid hydrolysis and iron catalysed oxidation. These phenomena are not only governed by the chemistry of the ink + cellulose system, but also by the penetration of the ink within the paper sheet. Here, we investigate ink penetration at the scale of a paper fibre using synchrotron-based STXM. This technique allows in situ mapping of the iron redox state and carbon speciation down to the sub-micrometre scale. Linen fibres have been impregnated by iron sulphate, gallic acid and gum Arabic; i.e. the three main ingredients of iron gall inks. Soft X-ray transparent ultrathin foils of impregnated fibres have been extracted using FIB milling. The data reported here evidence that ink components do not penetrate through the paper fibres the same way. In the absence of gum Arabic, gallic acid penetrates within the fibre but mostly remains in the outer part of the cell wall. A significant precipitation of Fe(III) gallate occurs during this migration whereas small amounts of iron (mostly Fe(II)) penetrate through the inner part of the fibre. The addition of gum Arabic as a binder makes the ink more viscous and significantly jeopardizes its ability to penetrate the fibre. The ink thus remains at the surface of the fibre. Low amounts of iron, essentially Fe(II), do still penetrate the fibre.

Photographic negative images on paper are certainly the earliest types of photographs ever produced, giving access to multiple photographic prints using a unique matrix. As early as 1841 in France, many variants of the paper negatives processes have been developed by skilled chemists and photographers covering a wide spectrum of practical and aesthetic concerns. Nowadays, due to their inherent historical and esthetical values, those negatives are getting an increasing interest from the art and museum community. However, their materiality has been poorly studied despite a large variety of processes involving many different chemicals and organic coatings; limiting our possibilities of identification, attribution or even preservation. The aim of this work was to develop a methodology to better assess the way those images were produced based on physical and chemical characteristics. A non-invasive approach combining optical, vibrational and X-ray spectroscopies was implemented on a collection of 138 historical images between 1841 and 1856 from French collections. A survey was carried out on these negatives to provide a series of relevant physical data (dimensions, thickness, weight, etc). Non-invasive reflectance FTIR showed great potentiality in revealing the presence of organic sizing (gelatin) or impregnation (wax). Multivariate analysis was applied on XRF data to help clustering negatives that have similar elemental composition and highlight relationships between makers. Finally, the morphological, physical and chemical results were all combined to answer historical questioning on the paper negative process.

Paper-based platforms for biological studies have received significant attention given that cellulose is ubiquitous, biocompatible, and can be readily organized into tunable fibrous structures. In the latter form, effect of complexity in surface morphologies (roughness, porosity and fiber organization) on cell-substrate interaction has not been thoroughly explored. We infer that altering the properties of a fibrous material should lead to significant changes in cellular microenvironment and direct the deposition of structurally analogous extracellular matrix (fiber-fiber templating) like collagen. Here, we elucidate the effect of varying paper roughness and surface chemistry on NIH/3T3 fibroblasts via organization of excreted collagen. Collagen intensity was found to increase linearly with paper porosity, indicating a 3D culture platform. The intensity, however, decays over time due to biodegradation of the substrate. Stability can be improved by introducing fluorinated alkyl silanes to yield hydrophobic paper. This process concomitantly transforms the substrate to a 2D-like scaffold where collagen is predominantly assembled on the surface, thus changing the cellular microenvironment. Altering surface energy also led to fluctuations in collagen intensity and organization over time for smooth (calendered) paper substrates. We infer that the increased roughness improves collagen adsorption through capillary driven petal effect. In general, the influence of the substrate simultaneously affects its ability to host collagen and guide orientation. These findings offer insights into the effects of secondary structures and chemistry of fibrous polymeric materials on cell culture, which we propose as vital parameters when using paper-based platforms.

This paper reports the fabrication of capacitive humidity sensors by integrating a graphene oxide sensing layer inside paper substrates. Graphene oxide sheets were self-assembled on the papers’ fibers. A comparative study between several sensors with different concentrations of graphene oxide and different processing times in the graphene oxide suspension is reported. Its aim is to optimize the sensing layer in terms of concentration and thickness towards the fabrication of highly sensitive and porous sensors. The morphology of the fabricated sensors was characterized using scanning electron microscopy, their structure and chemical composition using Raman and infrared spectroscopies. The washability and mechanical strength of the graphene oxide coated paper were tested in water and in an ultrasonic bath. Last, the sensing capabilities of the fabricated devices were tested for a relative humidity ranging from 30% to 90% RH. The optimal sensor is highly porous, hydrophobic and exhibits a good response towards humidity with a low hysteresis. This work presents a low cost alternative for the use of polymers and coated-papers as substrates for flexible electronics. It is also a first step towards the integration of flexible electronics into substrates, which enables the fabrication of highly porous, economical and flexible devices ideal for air flow monitoring, e-dressings and e-textiles.

International audience; A growing fraction of the papers published by CCR and at SIGCOMM-sponsored conferences include artifacts such as software or datasets. Besides CCR, these artifacts were rarely evaluated. During the last months of 2018, we organised two different Artifacts Evaluation Committees to which authors could submit the artifacts of their papers for evaluation. The first one evaluated the papers accepted by Conext’18 shortly after the TPC decision. It assigned ACM reproducibility badges to 12 different papers. The second one evaluated papers accepted by CCR and any SIGCOMM-sponsored conference. 28 papers received ACM reproducibility badges. We report on the results of a short survey among artifacts authors and reviewers and provide some suggestions for future artifacts evaluations.

We present explorable multiverse analysis reports, a new approach to statistical reporting where readers of research papers can explore alternative analysis options by interacting with the paper itself. This approach draws from two recent ideas: i) multiverse analysis, a philosophy of statistical reporting where paper authors report the outcomes of many different statistical analyses in order to show how fragile or robust their findings are; and ii) explorable explanations, narratives that can be read as normal explanations but where the reader can also become active by dynamically changing some elements of the explanation. Based on five examples and a design space analysis, we show how combining those two ideas can complement existing reporting approaches and constitute a step towards more transparent research papers.

Sometimes the quality of a process is best expressed by a relationship between response variables and explanatory variables. Checking over the time the stability of such functional relationships using statistical methods is called “profile monitoring”. Since 2007, when a detailed review paper in the field of profile monitoring was presented, an increasing number of papers have been published in this area. In this paper, we present a conceptual classification scheme and classify the papers in this area since 2008 up to 2018. The relevant papers are categorized and analyzed under different metrics and directions for future studies are recommended.

This artifact includes source code, scripts and datasets required to reproduce the experimental figures in the evaluation of the MM'18 paper, which is entitled "MiniView Layout for Bandwidth-Efficient 360-Degree Video". The artifact reports the comparison results among the standard cube layout (CUBE), the equi-angular layout (EAC), and the MiniView layout (MVL) in terms of compressed video size, visual quality of views and decoding and rendering time.

International audience; In 2019, Rhoban Football Club reached the first place of the KidSize soccer competition for the fourth time and performed the first in-game throw-in in the history of the Humanoid league. Building on our existing code-base, we improved some specific functionalities, introduced new behaviors and experimented with original methods for labeling videos. This paper presents and reviews our latest changes to both software and hardware, highlighting the lessons learned during RoboCup.

International audience; In this article, we present the design and results of an electronically re-writable chipless RFID tag on paper substrate. This tag consists of two resonators build around a modified shorted dipole, integrated with a non-volatile Metal-Insulator-Metal (MIM) switch, which tunes the electrical length of each resonator to resonate at two different frequencies, depending on state of the switch. One can electronically reconfigure the tag using low power DC pulses to change its RF signature. The integrated MIM switch has a layer architecture of Silver-Nafion-Aluminum, formed exclusively using an in-house process in ambient laboratory conditions, notably without the use of any 'clean room' facilities. Operating mechanism of the tag is validated with the help of developed electrical equivalent model. This study proves the concept of realizing 'electronically reconfigurable' chipless tags on flexible and low cost substrates, with a fabrication process compatible with mass production.

International audience

International audience; This book constitutes the thoroughly refereed proceedings of the First International Conference on Machine Learning for Networking, MLN 2018, held in Paris, France, in November 2018. The 22 revised full papers included in the volume were carefully reviewed and selected from 48 submissions. They present new trends in the following topics: Deep and reinforcement learning; Pattern recognition and classification for networks; Machine learning for network slicing optimization, 5G system, user behavior prediction, multimedia, IoT, security and protection; Optimization and new innovative machine learning methods; Performance analysis of machine learning algorithms; Experimental evaluations of machine learning; Data mining in heterogeneous networks; Distributed and decentralized machine learning algorithms; Intelligent cloud-support communications, resource allocation, energy-aware/green communications, software defined networks, cooperative networks, positioning and navigation systems, wireless communications, wireless sensor networks, underwater sensor networks.

International audience; Chitosan is a biopolymer obtained from chitin, one of the most abundant and renewable materials on Earth. Chitin is a primary component of cell walls in fungi, the exoskeletons of arthropods such as crustaceans, e.g., crabs, lobsters and shrimps, and insects, the radulae of molluscs, cephalopod beaks, and the scales of fish and lissamphibians. The discovery of chitin in 1811 is attributed to Henri Braconnot while the history of chitosan dates back to 1859 with the work of Charles Rouget. The name of chitosan was, however, introduced in 1894 by Felix Hoppe-Seyler. Chitosan has attracted major scientific and industrial interests from the late 1970s due to its particular macromolecular structure, biocompatibility, biodegradability and other intrinsic functional properties. Chitosan and derivatives have practical applications in the food industry, agriculture, pharmacy, medicine, cosmetology, textile and paper industries, and in chemistry. In recent years, chitosan has also received much attention in dentistry, ophthalmology, biomedicine and bioimaging, hygiene and personal care, veterinary medicine, packaging industry, agrochemistry, aquaculture, functional textiles and cosmetotextiles, catalysis, chromatography, beverage industry, photography, wastewater treatment and sludge dewatering, and biotechnology. Nutraceuticals and cosmeceuticals are actually growing markets, and therapeutic and biomedical products should be the next markets in the development of chitosan. Chitosan is also the object of numerous fundamental studies. In this review, we highlight a selection of works on chitosan applications published over the past two decades.

Water-based inks were formulated using cellulose nanofibers as a binder in order to directly front/reverse print lithium ion cells on a paper separator. Moreover, the high cohesion of electrodes as provided by cellulose nanofibers allowed for the embedding metallic current collectors in the electrodes during the printing stage, in order to develop a one-step printing and assembling process. Positive and negative inks based on LiFePO4, or graphite, respectively, and cellulose nanofibers, displayed rheological properties complying with a variety of printing processes, as well as with screen printing. Printed cells exhibited high electrical conductivity and adhesion between current collectors and inks, i.e., up to 64 &plusmn, 1 J/m2. Electrochemical cycling tests at C/10 showed a reversible capacity during the first cycle of about 80 mAh/g, which slightly decayed upon cycling. Preliminary results and assembling strategies can be considered as promising, and they represent a quick solution for the manufacturing of lithium ion batteries. Work is in progress to improve these processing issues and the cycling performances of Li-ion cells.

International audience; Photographic paper texture characterization constitutes a challenging image processing task and an important stake both for manufacturers and art museums. The present contribution shows how the Hyperbolic Wavelet Transform, thanks to its joint multiscale and anisotropie nature, permits to achieve an accurate photographic paper texture analysis and characterization. A cepstral-type distance, constructed on the coefficients of the Hyperbolic Wavelet Transform, is then used to measure similarity between pairs of paper textures. Spectral clustering followed by Ascendant Hierarchical Clustering applied to the similarity matrix enables an unsupervised classification of photographic paper sheets. This methodology is applied to a test dataset made available in the framework of the Historic Photographic Paper Classification Challenge. The relevance of the proposed texture characterization and classification procedure is assessed by comparisons against the database documentation provided by experts.