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Alarm floods are dangerous because the quantity of alarms triggered is too numerous for operators to reliably implement the right corrective action. Process operators of complex systems, such as chemical plants or nuclear power production, are faced with alarm management systems that can be better built in consideration of human capabilities and limitations. Developing human-machine interfaces (HMIs) that better support operators is critical for ensuring the safe and reliable operation of critical systems and processes. The research team has developed an accessible and adaptable prototyping environment dedicated for research on alarm management and human-machine interactions in the process industry. The method used was to build on the Tennessee Eastman Process (TEP) simulator and incorporate Human-Machine design guidelines. The results are an open-sourced prototyping environment that incorporates data from a real chemical plant and integrates true alarm data and thresholds. At the end of this article, we share the Github link to the entire MATLAB, Simulink and App Designer files of PER4Mance: a prototyping environment for research on human-machine interactions for alarm flood management.

In a companion paper by Cohen-Adad et al. we introduce the spine generic quantitative MRI protocol that provides valuable metrics for assessing spinal cord macrostructural and microstructural integrity. This protocol was used to acquire a single subject dataset across 19 centers and a multi-subject dataset across 42 centers (for a total of 260 participants), spanning the three main MRI manufacturers: GE, Philips and Siemens. Both datasets are publicly available via git-annex. Data were analysed using the Spinal Cord Toolbox to produce normative values as well as inter/intra-site and inter/intra-manufacturer statistics. Reproducibility for the spine generic protocol was high across sites and manufacturers, with an average inter-site coefficient of variation of less than 5% for all the metrics. Full documentation and results can be found at https://spine-generic.rtfd.io/. The datasets and analysis pipeline will help pave the way towards accessible and reproducible quantitative MRI in the spinal cord., Measurement(s)spinal cordTechnology Type(s)magnetic resonance imagingFactor Type(s)manufacturer • siteSample Characteristic - OrganismHomo sapiensSample Characteristic - LocationCanada • Switzerland • Australia • United States of America • United Kingdom • Germany • French Republic • Czech Republic • Italy • Japan • Kingdom of Spain • China Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14052269

The paper presents experimental results concerning the comparison of tensile and compressive basic creep behaviours at early ages of two different concretes: a normal strength concrete (NSC) and a very high strength fibre reinforced concrete (HPFRC). This research project has been done in the context of a bilateral collaboration between Polytechnique Montreal and IFSTTAR. Observations on the HPFRC showed specific compressive creep similar to the specific tensile creep. Moreover, the specific creep curves obtained under compressive and tensile loading had always positive values, i.e. they were in same direction of the applied load on specimens. Measurements made on the NSC revealed specific compressive creep with positive values (in the loading direction). However, specific tensile creep presented negative values (opposite direction of loading) for a long period. A physical explanation based on the existence of two mechanisms with opposite effect is proposed to describe these basic creep results. The first mechanism is a coupling between the microcracking process and the water transfers that lead to additional self-drying shrinkage; the second mechanism is the self-healing of concrete induced by the microcracking.

International audience; The charge and electron transport properties of molten ionic systems are among the most relevant properties to consider in the control of several electrochemical processes. First-principles-based equilibrium molecular dynamics (EMD) can provide reliable predictions of both the total and partial charge transport properties. In this work we calculate the charge transport properties of the electrolytic bath (Na 3 AlF 6-AlF 3-Al 2 O 3) of the Hall-Héroult electrolysis cells. We predict both the individual and collective charge transport properties (total, partial conductivity and self diffusion coefficients) for 11 different compositions typical of industrial conditions via a series of EMD simulations. The predicted total and partial ionic conductivities and their composition dependence are compared to available experimental data. A good agreement is obtained for all studied compositions. From a more fundamental point of view, the microscopic aspect of the charge transport properties of cryolitic melts is discussed through its correlation to the local structure of different melts. Deviations between the calculated partial conductivities and those derived via the Nernst-Einstein approximation can be explained by the presence of strong short-range ordering within the melts.

Made available in DSpace on 2022-04-28T19:51:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 This work proposes an approach combining artificial neural networks (ANN) with statistical models to predict injection processing conditions for four reinforcement architectures: plain weave, bidirectional noncrimp fabrics, unidirectional fabrics (Uni) and random fiber mats (Random). Key results allow evaluating the velocity of the flow front by combining processing parameters and creating a three-dimensional response surface based on a properly trained ANN. This investigation is based on a large number of experimental results. The key role played by some physical parameters was associated with predicting the impregnation behavior (velocity of the flow front) during resin injection. The main outcome aims to provide a better control of void content in terms of size and position to the four fibrous reinforcements considered. Department of Materials and Technology São Paulo State University, São paulo Department of Mechanical Engineering Aalto University Advanced Composites Research Group School of Mechanical and Aerospace Engineering Queen's University Belfast PPGE3M Federal University of Rio Grande do Sul Department of Material Engineering Federal University for Latin American Integration (UNILA) Foz do Iguaçu Department of Mechanical Engineering Research Center for High Performance Polymer and Composite Systems Polytechnique Montréal Department of Materials and Technology São Paulo State University, São paulo

Funding Information: Data acquisition was supported by the National Institute of Mental Health (R01-MH045573, P50-MH106435). Additional research support was provided by the National Institute of Biomedical Imaging and Bioengineering (R01-EB021265) and the National Institute of Neurological Disorders and Stroke (R01-NS119911). Imaging was carried out at the Athinoula A. Martinos Center for Biomedical Imaging at the Massachusetts General Hospital, using resources provided by the Center for Functional Neuroimaging Technologies, P41-EB015896, a P41 Biotechnology Resource Grant, and instrumentation supported by the NIH Shared Instrumentation Grant Program (S10RR016811, S10RR023401, S10RR019307, and S10RR023043). Andrey Zhylka is supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant (765148). Ye Wu and Pew-Thian Yap were supported in part by the National Institute of Mental Health (R01-MH125479), and the National Institute of Biomedical Imaging and Bioengineering (R01-EB008374). The team at Boston Children's Hospital was supported in part by the National Institutes of Health (NIH) grants R01-NS106030, R01-EB031849, and R01-EB019483. Team from UW-Madison would like to acknowledge the NIH grants R01NS123378, U54HD090256, R01NS092870, R01EB022883, R01AI117924, R01AG027161, RF1AG059312, P50AG033514, R01NS105646, UF1AG051216, R01NS111022, R01NS117568, P01AI132132, R01AI138647, R34DA050258, and R01AG037639. Erick J. Canales-Rodríguez was supported by the Swiss National Science Foundation, Ambizione grant PZ00P2_185814. Matteo Mancini was funded by the Wellcome Trust through a Sir Henry Wellcome Postdoctoral Fellowship [213722/Z/18/Z]. Publisher Copyright: © 2022 Limitations in the accuracy of brain pathways reconstructed by diffusion MRI (dMRI) tractography have received considerable attention. While the technical advances spearheaded by the Human Connectome Project (HCP) led to significant improvements in dMRI data quality, it remains unclear how these data should be analyzed to maximize tractography accuracy. Over a period of two years, we have engaged the dMRI community in the IronTract Challenge, which aims to answer this question by leveraging a unique dataset. Macaque brains that have received both tracer injections and ex vivo dMRI at high spatial and angular resolution allow a comprehensive, quantitative assessment of tractography accuracy on state-of-the-art dMRI acquisition schemes. We find that, when analysis methods are carefully optimized, the HCP scheme can achieve similar accuracy as a more time-consuming, Cartesian-grid scheme. Importantly, we show that simple pre- and post-processing strategies can improve the accuracy and robustness of many tractography methods. Finally, we find that fiber configurations that go beyond crossing (e.g., fanning, branching) are the most challenging for tractography. The IronTract Challenge remains open and we hope that it can serve as a valuable validation tool for both users and developers of dMRI analysis methods.

International audience

International audience; This paper emphasizes the importance of integrating outlet discharge and observed internal variables in the evaluation of distributed hydrological models outputs. It proposes a general methodology for a diagnostic evaluation of a complex distributed hydrological model, based on discharge data at the outlet and additional distributed information such as water level and surface soil moisture data. The proposed methodology is illustrated using the PUMMA model in the Mercier sub-catchment (6.6 km 2 ). Model parameters are specified according to field data and a previous study performed in a neighbouring catchment (Jankowfsky et al., 2014), without calibration. The distributed water level and soil moisture network of sensors were useful in the model evaluation process. Thus, model parameters are specified either using in situ information or results from previous studies. A stepwise approach is used for model evaluation. It includes standard water balance assessment as well as comparison of observed and simulated outlet discharge, whether on annual or event timescales. Soil moisture sensors are used to assess the ability of the model to simulate seasonal water storage dynamics based on a normalized index. The water level sensors network is used on two timescales: on a seasonal timescale, sensors network is used to assess the model's ability to simulate intermittency; whereas on event timescales, sensors network is used in determining the model's ability to reproduce observed reaction as well as response times. Event timescales do also focus on the correlation between hydrological response and either rainfall event or antecedent soil moisture variables. Results show that the non-calibrated model is quite effective at capturing water flow and soil water-storage dynamics, but it fails to reproduce observed runoff volume during events. There is strong indication of a deficiency in the characterization of catchment storage and upstream flowpath description. The soil water content and a network of water level sensors provide interesting information about soil moisture and river flow dynamics. They however fail to provide quantitative information about catchment storage. This study opens interesting perspectives for the evaluation of distributed hydrological models using hydrological signatures. Furthermore, it highlights the requirement of quantitative as well as qualitative signatures for improving such models.

International audience; Most transport models rely on a discrete description of space, and are, therefore, subject to spatial aggregation bias. Spatial aggregation induces the use of centroid connectors and the omission of intrazonal trips in traffic assignment. This practice is shown to bias main traffic assignment outcomes, especially in spatially coarse models. To address these modeling errors, the literature suggests some solutions but no clear-cut conclusion on the contribution of these solutions is available. In the current research, we undergo a detailed investigation of the contribution of some of these modeling solutions in order to provide useful and practical recommendations to academics and policy makers. Different assignment strategies that are deemed to mitigate the impacts of spatial aggregation in traffic assignment are explored in different case studies. Findings from this research outline that demand-side assignment strategies outperform supply-side methods in addressing the spatial aggregation problem. The results also suggest that the inclusion of intrazonal demand in traffic assignment is not sufficient to overcome aggregation biases. The definition of connectors is also of importance.

The FAO Livestock Environmental Assessment and Performance (LEAP) Partnership organised a Technical Advisory Group (TAG) to develop reference guidelines on water footprinting for livestock production systems and supply chains. The mandate of the TAG was to i) provide recommendations to monitor the environmental performance of feed and livestock supply chains over time so that progress towards improvement targets can be measured, ii) be applicable for feed and water demand of small ruminants, poultry, large ruminants and pig supply chains, iii) build on, and go beyond, the existing FAO LEAP guidelines and iv) pursue alignment with relevant international standards, specifically ISO 14040 (2006)/ISO 14044 (2006), and ISO 14046 (2014). The recommended guidelines on livestock water use address both impact assessment (water scarcity footprint as defined by ISO 14046, 2014) and water productivity (water use efficiency). While most aspects of livestock water use assessment have been proposed or discussed independently elsewhere, the TAG reviewed and connected these concepts and information in relation with each other and made recommendations towards comprehensive assessment of water use in livestock production systems and supply chains. The approaches to assess the quantity of water used for livestock systems are addressed and the specific assessment methods for water productivity and water scarcity are recommended. Water productivity assessment is further advanced by its quantification and reporting with fractions of green and blue water consumed. This allows the assessment of the environmental performance related to water use of a livestock-related system by assessing potential environmental impacts of anthropogenic water consumption (only “blue water”); as well as the assessment of overall water productivity of the system (including “green” and “blue water” consumption). A consistent combination of water productivity and water scarcity footprint metrics provides a complete picture both in terms of potential productivity improvements of the water consumption as well as minimizing potential environmental impacts related to water scarcity. This process resulted for the first time in an international consensus on water use assessment, including both the life-cycle assessment community with the water scarcity footprint and the water management community with water productivity metrics. EEA Rafaela Fil: Boulay, Anne-Marie. Sherbrooke University. LIRIDE; Canadá. Fil: Boulay, Anne-Marie. Polytechnique Montreal. CIRAIG; Canadá Fil: Drastig, Katrin. Leibniz Institute for Agricultural Engineering and Bioeconomy; Alemania Fil: Amanullah. University of Agriculture Peshawar. Faculty of Crop Production Sciences. Department of Agronomy; Paquistán Fil: Chapagain, Ashok. Pacific Institute; Estados Unidos Fil: Charlon, Veronica. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina Fil: Civit, Bárbara. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ambiente, Hábitat y Energía; Argentina Fil: DeCamillis, Camillo. Food and Agriculture Organization of the United Nations (FAO); Italia Fil: Souza, Marlos De. Food and Agriculture Organization of the United Nations (FAO); Italia Fil: Hess, Tim. Cranfield University. Cranfield Water Science Institute; Reino Unido Fil: Hoekstra, Arjen Y. University of Twente. Twente Water Centre; Holanda Fil: Hoekstra, Arjen Y. National University of Singapore. Lee Kuan Yew School of Public Policy. Institute of Water Policy; Singapur Fil: Ibidhi, Ridha. National Institute of Agronomic Research of Tunisia. Department of Animal and Forage Production; Túnez Fil: Lathuillière, Michael J. Stockholm Environment Institute; Suecia Fil: Lathuillière, Michael J. University of British Columbia. Institute for Resources, Environment and Sustainability; Canadá Fil: Manzardo, Alessandro. University of Padova. Department of Industrial Engineering. CESQA; Italia Fil: McAllister, Tim. Lethbridge Research and Development Centre. Agriculture and Agri-Food Canada; Canadá Fil: Morales, Ricardo A. AgroDer SC; México Fil: Motoshita, Masaharu. National Institute of Advanced Industrial Science and Technology. Institute of Science for Safety and Sustainability; Japón Fil: Palhares, Julio Cesar Pascale. Embrapa Southeast Livestock; Brasil Fil: Pirlo, Giacomo. Research Centre for Animal Production and Aquaculture. Council for Agricultural Research and Economics; Italia Fil: Ridoutt, Brad. University of the Free State. Department Agricultural Economics; Sudáfrica Fil: Ridoutt, Brad. Commonwealth Scientific and Industrial Research Organisation (CSIRO). Agriculture and Food; Australia Fil: Russo, Valentina. University of Cape Town. Department of Chemical Engineering. Environmental and Process Systems Engineering Research Group; Sudáfrica Fil: Salmoral, Gloria. Cranfield University. Cranfield Water Science Institute; Reino Unido Fil: Salmoral, Gloria. University of Exeter. Environment and Sustainability Institute; Reino Unido Fil: Salmoral, Gloria. University of Exeter. College of Engineering, Mathematics and Physical Sciences; Reino Unido Fil: Singh, Ranvir. Massey University. School of Agriculture and Environment; Nueva Zelanda Fil: Vanham, Davy. Joint Research Centre. European Commission; Italia Fil: Wiedemann, Stephen. Integrity Ag and Environment; Australia Fil: Weichao, Zheng. China Agricultural University; China Fil: Pfister, Stephan. ETH-Zürich. Department of Civil, Environmental and Geomatic Engineering; Suiza

International audience; The application of functional near-infrared spectroscopy (fNIRS) in the neurosciences has been expanding over the last 40 years. Today, it is addressing a wide range of applications within different populations and utilizes a great variety of experimental paradigms. With the rapid growth and the diversification of research methods, some inconsistencies are appearing in the way in which methods are presented, which can make the interpretation and replication of studies unnecessarily challenging. The Society for Functional Near-Infrared Spectroscopy has thus been motivated to organize a representative (but not exhaustive) group of leaders in the field to build a consensus on the best practices for describing the methods utilized in fNIRS studies. Our paper has been designed to provide guidelines to help enhance the reliability, repeatability, and traceability of reported fNIRS studies and encourage best practices throughout the community. A checklist is provided to guide authors in the preparation of their manuscripts and to assist reviewers when evaluating fNIRS papers. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

The flight envelope of civil aircraft is bounded by several aerodynamic phenomena, of which the stall and the transonic buffet. Stall is defined as a loss of lift caused by flow separation, while the transonic buffet is an unsteady phenomenon resulting from the interaction between a shock wave and a separated boundary layer. In both cases, three-dimensional features named respectively stall cells and buffet cells are observed experimentally and numerically. In buffet condition they are linked to a higher frequency in 3D than in 2D.This thesis aims to improve the knowledge of these phenomena. First, Unsteady Reynolds Navier-Stokes simulations and Zonal Detached Eddy Simulations are used to characterize the three-dimensional stall and buffet over infinite swept wings. These analyses show the occurrence of cellular patterns which are stationary for unswept wings and convected when the wing is swept. Then, global stability analyses are used to study the transition between a two-dimensional flow and the three-dimensional condition with cells. These analyses exhibit a similar unstable mode between the two flow regimes, thus explaining the occurrence of the cells. At last, a low order model relying on a lifting surface model is used to explain the stall cells. This model exhibits an instability which causes the flow to become three-dimensional when the lift slopes are negative. Together these results lead to think that the buffet cells are caused by an instability akin to the stall cell one and to question the usual interpretation of the 3D buffet.; L’enveloppe de vol des aéronefs civils est limitée par plusieurs phénomènes aérodynamiques. Parmi ceux-ci figurent le décrochage et le tremblement transsonique. Le décrochage est une perte de portance causée par la séparation de l’écoulement à forte incidence, alors que le tremblement est une instationnarité de l’interaction entre une onde de choc et la couche limite séparée. Dans ces deux conditions, des effets tridimensionnels appelés respectivement cellules de décrochage et cellules de tremblement sont observés. En condition transsonique, ces dernières sont associées à des fréquences de tremblement plus élevées en3D qu’en 2D. Le but de cette thèse est d’améliorer la compréhension de ces phénomènes. Des simulations des équations Reynolds-Averaged Navier-Stokes et des Zonal Detached Eddy Simulations sont utilisées pour caractériser ces phénomènes sur des ailes en flèche infinie. Ces analyses montrent des cellules statiques pour les ailes sans flèche, et leur convection lorsque l’aile est en flèche. Par la suite, des analyses de la stabilité globale sont utilisées pour étudier la transition entre l’état 2D et 3D. Un mode instable similaire est observé entre les deux régimes d’écoulement, expliquant ainsi la présence de ces cellules. Finalement, un modèle basse-fidélité basé sur la théorie des surfaces portantes est utilisé. Ce dernier prédit les cellules de décrochage lorsque la pente du coefficient de portance est négative. Ces résultats indiquent que les cellules de tremblement sont causées par une instabilité analogue à celle causant les cellules de décrochage. On peut ainsi remettre en question l’interprétation classique du tremblement 3D.

Designing effective, usable, and widely adoptable stroke gesture commands for graphical user interfaces is a challenging task that traditionally involves multiple iterative rounds of prototyping, implementation, and follow-up user studies and controlled experiments for evaluation, verification, and validation. An alternative approach is to employ theoretical models of human performance, which can deliver practitioners with insightful information right from the earliest stages of user interface design. However, very few aspects of the large spectrum of human performance with stroke gesture input have been investigated and modeled so far, leaving researchers and practitioners of gesture-based user interface design with a very narrow range of predictable measures of human performance, mostly focused on estimating production time, of which extremely few cases delivered accompanying software tools to assist modeling. We address this problem by introducing "Omnis Praedictio" (OMNISfor short), a generic technique and companion web tool that provides accurate user-independent estimations of any numerical stroke gesture feature, including custom features specified in code. Our experimental results on three public datasets show that our model estimations correlate on average r(s) > 0.9 with groundtruth data. OMNISalso enables researchers and practitioners to understand human performance with stroke gestures on many levels and, consequently, raises the bar for human performance models and estimation techniques for stroke gesture input.

Purpose Life cycle assessment (LCA) has been used to assess freshwater-related impacts according to a new water footprint framework formalized in the ISO 14046 standard. To date, no consensus-based approach exists for applying this standard and results are not always comparable when different scarcity or stress indicators are used for characterization of impacts. This paper presents the outcome of a 2-year consensus building process by the Water Use in Life Cycle Assessment (WULCA), a working group of the UNEP-SETAC Life Cycle Initiative, on a water scarcity midpoint method for use in LCA and for water scarcity footprint assessments. Methods In the previous work, the question to be answered was identified and different expert workshops around the world led to three different proposals. After eliminating one proposal showing low relevance for the question to be answered, the remaining two were evaluated against four criteria: stakeholder acceptance, robustness with closed basins, main normative choice, and physical meaning. Results and discussion The recommended method, AWARE, is based on the quantification of the relative available water remaining per area once the demand of humans and aquatic ecosystems has been met, answering the question “What is the potential to deprive another user (human or ecosystem) when consuming water in this area?” The resulting characterization factor (CF) ranges between 0.1 and 100 and can be used to calculate water scarcity footprints as defined in the ISO standard. Conclusions After 8 years of development on water use impact assessment methods, and 2 years of consensus building, this method represents the state of the art of the current knowledge on how to assess potential impacts from water use in LCA, assessing both human and ecosystem users’ potential deprivation, at the midpoint level, and provides a consensus-based methodology for the calculation of a water scarcity footprint as per ISO 14046. ISSN:0948-3349 ISSN:1614-7502

This paper presents a cooperative distributed model for the control of product flow in a network of cooperative inventory systems (ISs). In each IS, a linear input/output equation describes the balance between product demand vs production, as well as the product flows among ISs. The peculiarity of the problem is that both the production and demand are stochastic and cannot be controlled. In addition, each IS has just deterministic information on its inventory level (i.e., the quantity of stored product) which is not shared in the network. Other information is available in each IS regarding the forecast of both its related production and demand. The goal of the proposed model, on the overall network, is to keep both the product stored in each IS and the product exchanged among ISs, around given values as planned a priori. The only available control is related to the product flow between neighboring ISs, which has to be locally computed. Section II describes the proposed approach, which is based on the dual decomposition of the problem, which enables reaching the optimal control. This problem can represent the abstraction of a series of problems, which are not just related to logistics. As examples, section III presents two case studies: a network of virtual power utilities; and the control of risk in the transport of dangerous goods by road.

Objective: Our aim is to establish methods for quantifying morphometric properties of calcified cartilage (CC) from micro-computed tomography (mu CT). Furthermore, we evaluated the feasibility of these methods in investigating relationships between osteoarthritis (OA), tidemark surface morphology and open subchondral channels (OSCCs). Method: Samples (n = 15) used in this study were harvested from human lateral tibial plateau (n = 8). Conventional roughness and parameters assessing local 3-dimensional (3D) surface variations were used to quantify the surface morphology of the CC. Subchondral channel properties (percentage, density, size) were also calculated. As a reference, histological sections were evaluated using Histopathological osteoarthritis grading (OARSI) and thickness of CC and subchondral bone (SCB) was quantified. Results: OARSI grade correlated with a decrease in local 3D variations of the tidemark surface (amount of different surface patterns (r(s) = -0.600, P = 0.018), entropy of patterns (EP) (r(s) = -0.648, P = 0.018), homogeneity index (HI) (r(s) = 0.555, P = 0.032)) and tidemark roughness (TMR) (r(s) = -0.579, P = 0.024). Amount of different patterns (ADP) and EP associated with channel area fraction (CAF) (r(p) = 0.876, P

Metasurfaces are thin two-dimensional metamaterial layers that allow or inhibit the propagation of electromagnetic waves in desired directions. For example, metasurfaces have been demonstrated to produce unusual scattering properties of incident plane waves or to guide and modulate surface waves to obtain desired radiation properties. These properties have been employed, for example, to create innovative wireless receivers and transmitters. In addition, metasurfaces have recently been proposed to confine electromagnetic waves, thereby avoiding undesired leakage of energy and increasing the overall efficiency of electromagnetic instruments and devices. The main advantages of metasurfaces with respect to the existing conventional technology include their low cost, low level of absorption in comparison with bulky metamaterials, and easy integration due to their thin profile. Due to these advantages, they are promising candidates for real-world solutions to overcome the challenges posed by the next generation of transmitters and receivers of future high-rate communication systems that require highly precise and efficient antennas, sensors, active components, filters, and integrated technologies. This Roadmap is aimed at binding together the experiences of prominent researchers in the field of metasurfaces, from which explanations for the physics behind the extraordinary properties of these structures shall be provided from viewpoints of diverse theoretical backgrounds. Other goals of this endeavour are to underline the advantages and limitations of metasurfaces, as well as to lay out guidelines for their use in present and future electromagnetic devices. This Roadmap is divided into five sections: 1. Metasurface based antennas. In the last few years, metasurfaces have shown possibilities for advanced manipulations of electromagnetic waves, opening new frontiers in the design of antennas. In this section, the authors explain how metasurfaces can be employed to tailor the radiation properties of antennas, their remarkable advantages in comparison with conventional antennas, and the future challenges to be solved. 2. Optical metasurfaces. Although many of the present demonstrators operate in the microwave regime, due either to the reduced cost of manufacturing and testing or to satisfy the interest of the communications or aerospace industries, part of the potential use of metasurfaces is found in the optical regime. In this section, the authors summarize the classical applications and explain new possibilities for optical metasurfaces, such as the generation of superoscillatory fields and energy harvesters. 3. Reconfigurable and active metasurfaces. Dynamic metasurfaces are promising new platforms for 5G communications, remote sensing and radar applications. By the insertion of active elements, metasurfaces can break the fundamental limitations of passive and static systems. In this section, we have contributions that describe the challenges and potential uses of active components in metasurfaces, including new studieson non-Foster, parity-time symmetric, and non-reciprocal metasurfaces. 4. Metasurfaces with higher symmetries. Recent studies have demonstrated that the properties of metasurfaces are influenced by the symmetries of their constituent elements. Therefore, by controlling the properties of these constitutive elements and their arrangement, one can control the way in which the waves interact with the metasurface. In this section, the authors analyze the possibilities of combining more than one layer of metasurface, creating a higher symmetry, increasing the operational bandwidth of flat lenses, or producing cost-effective electromagnetic bandgaps. 5. Numerical and analytical modelling of metasurfaces. In most occasions, metasurfaces are electrically large objects, which cannot be simulated with conventional software. Modelling tools that allow the engineering of the metasurface properties to get the desired response are essential in the design of practical electromagnetic devices. This section includes the recent advances and future challenges in three groups of techniques that are broadly used to analyze and synthesize metasurfaces: circuit models, analytical solutions and computational methods.

International audience; This paper emphasizes the importance of integrating outlet discharge and observed internal variables in the evaluation of distributed hydrological models outputs. It proposes a general methodology for a diagnostic evaluation of a complex distributed hydrological model, based on discharge data at the outlet and additional distributed information such as water level and surface soil moisture data. The proposed methodology is illustrated using the PUMMA model in the Mercier sub-catchment (6.6 km 2 ). Model parameters are specified according to field data and a previous study performed in a neighbouring catchment (Jankowfsky et al., 2014), without calibration. The distributed water level and soil moisture network of sensors were useful in the model evaluation process. Thus, model parameters are specified either using in situ information or results from previous studies. A stepwise approach is used for model evaluation. It includes standard water balance assessment as well as comparison of observed and simulated outlet discharge, whether on annual or event timescales. Soil moisture sensors are used to assess the ability of the model to simulate seasonal water storage dynamics based on a normalized index. The water level sensors network is used on two timescales: on a seasonal timescale, sensors network is used to assess the model's ability to simulate intermittency; whereas on event timescales, sensors network is used in determining the model's ability to reproduce observed reaction as well as response times. Event timescales do also focus on the correlation between hydrological response and either rainfall event or antecedent soil moisture variables. Results show that the non-calibrated model is quite effective at capturing water flow and soil water-storage dynamics, but it fails to reproduce observed runoff volume during events. There is strong indication of a deficiency in the characterization of catchment storage and upstream flowpath description. The soil water content and a network of water level sensors provide interesting information about soil moisture and river flow dynamics. They however fail to provide quantitative information about catchment storage. This study opens interesting perspectives for the evaluation of distributed hydrological models using hydrological signatures. Furthermore, it highlights the requirement of quantitative as well as qualitative signatures for improving such models.

2D non-uniform polygonal meshes allow representation of the impact of landscape elements and small infrastructures on water flows. The initial vectorial mesh, derived from the intersection of several geographical information systems' layers, can have highly non-convex or sliver polygons. These bad-shaped elements compromise accurate numerical flow computation. We propose a flexible divide-and-conquer strategy to decompose polygons into physiographical meaningful parts using shape descriptors to better represent the surface terrain and hydrologic connectivity. We use the convexity index (CI) and the form factor (FF) to consider convex and square like optimum shapes. The strategy was applied to two peri-urban areas whose hydrologic response was simulated using distributed modeling. Good-quality meshes were generated with threshold values of CI≈0.8 and FF≈0.2, and CI≈0.95 and FF≈0.4 for undeveloped and highly urbanized zones, respectively. We concluded that the mesh segmentation facilitates the representation of the spatially distributed processes controlling not only the lumped response of the catchment, but also the spatial variability of water quantity and fluxes within it at medium and small scales.