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To reduce CO2 and pollutant emissions, automotive manufacturers tend to turn increasingly toward electrified powertrains solutions, such as Hybrid Vehicles (HEV). Model Based System Engineering (MBSE) and computational tools are useful to support the development of HEV systems. System architectures need to be investigated to find optimal solutions regarding multiple possible goals constraints (fuel consumption, CO2 emissions, etc.). In this study, a novel global optimization framework is proposed to enable an automated cooling system optimization. The methodology starts with a set of components, design rules, and system requirements to search and automatically generate all the admissible cooling system architectures. System architectures are generated by a concept of decision tree. The decision tree algorithm is coupled to a design rules database to avoid exploring solutions that do not satisfy system requirements. Hydraulic models are automatically built for each system architecture generated to optimize head losses and minimize the pump consumption. For the most interesting solutions, 3D piping geometrical data (lengths, angles, and curve radius) are automatically drawn by a 3D optimization tool. Piping geometrical data are integrated in GT-SUITE thermo-hydraulic simulation models automatically built to evaluate the most interesting cooling system architectures generated. The best candidates are identified by a multi-criteria decision-making strategy. A first case of conventional vehicle cooling system is studied. Results on the given example indicate that the difference of energy consumption on WLTC cycle between the best performing architecture and the worst one is 69%.

The French coast of the Eastern English Channel (ECC) is classified as potential eutrophication zone by the Paris and Oslo Convention (OSPAR), and as moderate to poor according to phytoplankton quality element of the Water Framework Directive (WFD). Indeed, the French part of the EEC is regularly affected by Phaeocystis globosa bloom events, which have detrimental effects on the marine ecosystem, economy as well as public health. Since phytoplankton is an important indicator of water quality, the MAREL Carnot oceanographic multi-sensor station was installed in the Eastern English Channel at the Carnot wall in Boulogne sur Mer in 2004 to monitor water quality and phytoplankton in order to complement results from existing more conventional low resolution monitoring programs, with high frequency data (sampling every 20 minutes). The purpose of this paper is to introduce the MAREL Carnot dataset and show how it can be used for several research objectives. MAREL Carnot collects high frequency, multi-parameter observations from surface water, as well as meteorological measurements, and send data almost immediately to an inshore data center. In this paper, we present several physiochemical and biological parameters measured by this station. In addition, we demonstrated, based on previous research activities, that the MAREL Carnot dataset is useful for evaluating environmental or ecological statuses, marine phytoplankton ecology, physical oceanography, turbulence, as well as public policy. Most importantly, we showed its contribution to Marine Strategy Framework Directive (MSFD) and other regional or universal conventions.

This article describes the historical data series produced by the SRN network managed by Ifremer. Since 1992, the SRN (‘Suivi Régional des Nutriments’ in French; Regional Nutrients Monitoring Programme) network has been analysing phytoplankton species and measuring twelve physicochemical parameters at ten different stations distributed along three different transects located in the Eastern English Channel, and the Southern Bight of the North Sea. The SRN collects a maximum of 184 samples per year and detects up to 281 taxa, including harmful algal bloom species (HABs), with a bi-weekly to monthly sampling frequency (depending on the location and the season). The objectives of this monitoring program are to assess the influence of continental inputs on the marine environment, and their implications on possible eutrophication processes. It also aims to estimate the effectiveness of development and management policies in the marine coastal zone. The regular acquisition of data allows the establishment of a long-term monitoring of the evolution of coastal water quality, as well as the observation of the consequences of large-scale alterations and modifications that are more related to regional anthropogenic activities. This paper provides an overview of the main characteristics of SRN data (descriptive statistics and data series main patterns) as well as an analysis of temporal trends using specific numerical tools available as an R package to help make use of such data. Main results of several research projects are also highlighted providing the readers with examples of what is doable with such a data set.

Along with their important diversity, coastal ecosystems receive various amounts of nutrients, principally arising from the continent and from the related human activities (mainly industrial and agricultural activities). During the 20th century, nutrients loads have increased following the increase of both the global population and need of services. Alongside, climate change including temperature increase or atmospheric circulation change has occurred. These processes, Ecosystem state changes are hard to monitor and predict. To study the long-term changes of nutrients concentrations in coastal ecosystems, eleven French coastal ecosystems were studied over 20 years as they encompass large climatic and land pressures, representative of temperate ecosystems, over a rather small geographical area. Both univariate (time series decomposition) and multivariate (relationships between ecosystems and drivers) statistical analyses were used to determine ecosystem trajectories as well as typologies of ecosystem trajectories. It appeared that most of the French coastal ecosystems exhibited trajectories towards a decrease in nutrients concentrations. Differences in trajectories mainly depended on continental and human influences, as well as on climatic regimes. One single ecosystem exhibited very different trajectories, the Arcachon Bay with an increase in nutrients concentrations. Ecosystem trajectories based on ordination techniques were proven to be useful tools to monitor ecosystem changes. This study highlighted the importance of local environments and the need to couple uni- and multi-ecosystem studies. Although the studied ecosystems were influenced by both local and large-scale climate, by anthropogenic activities loads, and that their trajectories were mostly similar based on their continental influence, non-negligible variations resulted from their internal functioning.

The ATmospheric LIDAR (Light Detection and Ranging), ATLID, is part of the payload of the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) mission, the sixth Earth Explorer Mission of the European Space Agency (ESA) Living Planet Programme (http://esamultimedia.esa.int/docs/SP_1279_1_EarthCARE.pdf). The EarthCARE payload consists of four instruments that will, in a synergetic manner, retrieve vertical profiles of clouds and aerosols, and the characteristics of the radiative and micro-physical properties, to determine flux gradients within the atmosphere and top of atmosphere radiance and flux. ATLID’s task is to provide vertical profiles of optically thin cloud and aerosol layers, as well as the altitude of cloud boundaries. With that purpose ATLID emits

ATLID (ATmospheric LIDar) is the atmospheric backscatter LIDAR (Light Detection and Ranging) on board of the EarthCARE (Earth Cloud, Aerosol and Radiation Explorer) mission, the sixth Earth Explorer Mission of the ESA (European Space Agency) Living Planet Programme [1-5]. ATLID’s purpose is to provide vertical profiles of optically thin cloud and aerosol layers, as well as the altitude of cloud boundaries [6-10]. In order to achieve this objective ATLID emits short duration laser pulses in the UV, at a repetition rate of 51 Hz, while pointing in a near nadir direction along track of the satellite trajectory. The atmospheric backscatter signal is then collected by its 620 mm aperture telescope, filtered through the optics of the instrument focal plane assembly, in order to separate and measure the atmospheric Mie and Rayleigh scattering signals. With the completion of the full instrument assembly in 2019, ATLID has been subjected to an ambient performance test campaign, followed by a successful environmental qualification test campaign, including performance calibration and characterization in thermal vacuum conditions. In this paper the design and operational principle of ATLID is recalled and the major performance test results are presented, addressing the main key receiver and emitter characteristics. Finally, the estimated instrument, in-orbit, flight predictions are presented; these indicate compliance of the ALTID instrument performance against its specification and that it will meet its mission science objectives for the EarthCARE mission, to be launched in 2023.

The ATmospheric LIDAR (Light Detection and Ranging), ATLID, is part of the payload of the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) mission, the sixth Earth Explorer Mission of the European Space Agency (ESA) Living Planet Programme [1]. The EarthCARE payload consists of four instruments that will, in a synergetic manner, retrieve vertical profiles of clouds and aerosols, and the characteristics of the radiative and microphysical properties, to determine flux gradients within the atmosphere and top of atmosphere radiance and flux. ATLID's objective is to provide vertical profiles of optically thin cloud and aerosol layers, as well as the altitude of cloud boundaries. With that purpose ATLID emits

EarthCARE, the Earth Cloud Aerosol and Radiation Explorer, is the third Earth Explorer Core Mission of the European Space Agency's Earth Observation Envelope Programme. These are defined as major missions led by ESA to cover primary research objectives set out in the Living Planet Program. EarthCARE is being developed in cooperation with the Japan Aerospace Exploration Agency (JAXA), which is providing the Cloud Profiling Radar.

In the framework of ecological or environmental assessments and management, detection, characterization and forecasting of the dynamics of environmental states are of paramount importance. These states should reflect general patterns of change, recurrent or occasional events, long-lasting or short or extreme events which contribute to explain the structure and the function of the ecosystem. To identify such states, many scientific consortiums promote the implementation of Integrated Observing Systems which generate increasing amount of complex multivariate/multisource/multiscale datasets. Extracting the most relevant ecological information from such complex datasets requires the implementation of Machine Learning-based processing tools. In this context, we proposed a divisive spectral clustering architecture&mdash, the Multi-level Spectral Clustering (M-SC) which is, in this paper, extended with a no-cut criteria. This method is developed to perform detection events for data with a complex shape and high local connexity. While the M-SC method was firstly developed and implemented for a given specific case study, we proposed here to compare our new M-SC method with several existing direct and hierarchical clustering approaches. The clustering performance is assessed from different datasets with hard shapes to segment. Spectral methods are most efficient discovering all spatial patterns. For the segmentation of time series, hierarchical methods better isolated event patterns. The new M-SC algorithm, which combines hierarchical and spectral approaches, give promise results in the segmentation of both spatial UCI databases and marine time series compared to other approaches. The ability of our M-SC method to deal with many kinds of datasets allows a large comparability of results if applies within a broad Integrated Observing Systems. Beyond scientific knowledge improvements, this comparability is crucial for decision-making about environmental management.

The phytoplankton compartment is particularly reactive to changes in nutrient concentration and is used as a quality indicator. Using a simple numerical approach, the response of emblematic harmful taxa from the eastern English Channel and southern North Sea to changes in nutrient inputs was studied. The method is based on a diachronic approach using averaged maxima over sliding periods of six years (1994&ndash, 2018). This gave a final dataset containing pairs of points (number of years) for explained and explanatory variables. The temporal trajectory of the relationship between each pair of variables was then highlighted. Changes were represented as long-term trajectories that allowed a comparison to a reference/average situation. In addition, the relevance of the use of Phaeocystis globosa and the Pseudo-nitzchia complex as eutrophication species indicators was tested. Results showed a significant shift in the 2000s and different trajectories between diatoms and P. globosa abundances in response to changes in Dissolved Inorganic Nitrogen (DIN). The contrasting ecosystems under study reacted differently depending on the initial pressure. While a return to good ecological status does not seem feasible in the short term, it seems that these ecosystems were in an unstable intermediate state requiring continued efforts to reduce nutrient inputs.

[Departement_IRSTEA]Eaux [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples; International audience; Eutrophication is one of the most common causes of water quality impairment of inland and marine waters. Its best-known manifestations are toxic cyanobacteria blooms in lakes and waterways and proliferations of green macro algae in coastal areas. The term eutrophication is used by both the scientific community and public policy-makers, and therefore has a myriad of definitions. The introduction by the public authorities of regulations to limit eutrophication is a source of tension and debate on the activities identified as contributing or having contributed decisively to these phenomena. Debates on the identification of the driving factors and risk levels of eutrophication, seeking to guide public policies, have led the ministries in charge of the environment and agriculture to ask for a joint scientific appraisal to be conducted on the subject. Four French research institutes were mandated to produce a critical scientific analysis on the latest knowledge of the causes, mechanisms, consequences and predictability of eutrophication phenomena. This paper provides the methodology and the main findings of this two years exercise involving 40 scientific experts.

International audience; Automated pulse shape-recording flow cytometry was applied to address phytoplankton spatial distribution, at high frequency, in stratified and well mixed water masses in the Western and Central English Channel during the summer-fall transition. Cytometric pulse shapes derived from optical features of single cells allowed the characterization of eight phytoplankton groups. Abundance and total red fluorescence (chlorophyll a autofluorescence) per group were used to define six phytoplankton communities. Their distribution revealed high spatial heterogeneity. Abundance presented a longitudinal gradient for six over the eight groups and succession of brutal shifts along the cruise. Maximum values were often located near the Ushant front in the Western English Channel. A latitudinal gradient characterised the Central English Channel waters under the influence of the Seine estuary. Picophytoplankton (Synechococcus-like cells and picoeukaryotes) represented up to 96% of total abundance and half of the total red fluorescence of the communities near the main front and the Bay of Seine, whereas nanoeukaryotes and microphytoplankton, represented only 4% and less than 1% respectively of total abundance. Both nanoeukaryotes and microphytoplankton dominated the total red fluorescence of the communities of the Central English Channel. The study of traits within each group showed a high variability of traits between communities. The comparison between traits showed that they were independent from each other for some groups (size and red fluorescence per cell for PicoHighFLR and Coccolithophore-like cells; orange and red fluorescence for all the groups), whereas they were dependent for other groups (red fluorescence per cell was dependent of size for picophytoplankton, NanoLowFLR, NanoHighFLR, Cryptophyte-like cells and Microphytoplankton). Variance partitioning revealed that the environmental parameters (temperature, salinity and turbidity) accounted less than spatial descriptors (physical and biological processes) in shaping the communities. Hydrological structures (frontal structures, eddies and tidal streams) were responsible for patches of phytoplankton and defined the structure at the sub-mesoscale (1–10 km) in this area.

The influence of clouds on the incoming solar and reflected thermal radiation remains one of the most important climate uncertainties. The global observation of vertical profiles of cloud ice and liquid water with simultaneous and collocated solar and thermal flux observation will provide crucial data to address this uncertainty. Furthermore, collocated global observation of vertical profiles of aerosol types are required to address the direct and indirect effects of aerosol.In response to these needs, the European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), is implementing the Earth Cloud, Aerosol and Radiation Explorer Mission, EarthCARE.Vertical profiles of cloud ice and liquid water, aerosol type, precipitation, heating rates, solar and thermal top-of-atmosphere radiances and flux profiles will be synergistically derived from the observations of the satellite’s four instruments.Two active instruments are embarked, a cloud-aerosol lidar and a cloud Doppler radar. The Atmospheric Lidar (ATLID) operates at 355nm and is equipped with a high-spectral resolution receiver and depolarisation channel that separates molecular from particulate backscatter and distinguishes cloud and aerosol types. The Cloud Profiling Radar (CPR), provided by JAXA, is a highly sensitive W-band Doppler radar (94GHz) that measures cloud profiles, precipitation and vertical motion within clouds. The Doppler observation will measure vertical motion in clouds providing novel information on convection, precipitating ice particles and raindrop fall speed. Two passive instruments provide cloud and aerosol swath information and solar and thermal radiances and top-of-atmosphere fluxes. The Multi-Spectral Imager (MSI) has a 150km wide swath and seven channels in the visible, near-IR, short-wave IR, and thermal IR. The Broad-Band Radiometer (BBR) observes broad-band solar and thermal radiation reflected and emitted from the Earth, with three fixed fields of view: forward, nadir and backward.In preparation for the science exploitation of the mission, complex data retrieval algorithms in the Ground Segment will exploit the synergy of the four instruments and deliver a range of cloud, aerosol and radiation related data products, including three-dimensional cloud-aerosol-precipitation scenes, with collocated broad-band heating rate and radiation data, over a mission lifetime of three years.The presentation will provide an overview of the mission, main performances of the three ESA instruments and expected science data products.

International audience; The French initial assessment of the Marine Strategy Framework Directive (MSFD) highlighted the lack of reliable data concerning offshore areas. During the planning of the monitoring programmes, the scientists therefore proposed to partially cover this gap by using existing fisheries research vessel surveys deployed for the purposes of the Common Fisheries Policy (CFP). This paper describes ways of improving the effectiveness of these surveys and making them better suited to delivering the information needed for the MSFD. The process took two years and became operational at the beginning of the year 2016. Testing phases from October 2013 to August 2015 had to be organized to fit within the ongoing fisheries tasks without significantly increasing the workload in terms of both time and human resources. Six fisheries research surveys henceforth collect new data, with or without additional sampling techniques. Specific examples are given with litter and hydrological data which will be used to assess the environmental status of French marine waters. The paper also identifies certain limitations regarding this approach. This French experiment enabled more efficient and effective use of current data collection efforts, while optimising vessel time and implementing an ecosystem approach in collecting data for fisheries management.

The link between harmful algal blooms, phytoplankton community dynamics and global environmental change is not well understood. To tackle this challenging question, a new method was used to reveal how phytoplankton communities responded to environmental change with the occurrence of an harmful algae, using the coastal waters of the eastern English Channel as a case study. The great interannual variability in the magnitude and intensity of Phaeocystis spp. blooms, along with diatoms, compared to the ongoing gradual decrease in anthropogenic nutrient concentration and rebalancing of nutrient ratios; suggests that other factors, such as competition for resources, may also play an important role. A realized niche approach was used with the Outlying Mean Index analysis and the dynamics of the species’ realized subniches were estimated using the Within Outlying Mean Indexes calculations under low (L) and high (H) contrasting Phaeocystis spp. abundance. The Within Outlying Mean Indexes allows the decomposition of the realized niche into realized subniches, found within the subset of habitat conditions and constrained by a subset of a biotic factor. The two contrasting scenarios were characterized by significantly different subsets of environmental conditions and diatom species (BV-step analysis), and different seasonality in salinity, turbidity, and nutrients. The subset L environmental conditions were potentially favorable for Phaeocystis spp. but it suffered from competitive exclusion by key diatom species such as Skeletonema spp., Thalassiosira gravida, Thalassionema nitzschioides and the Pseudo-nitzchia seriata complex. Accordingly, these diatoms species occupied 81% of Phaeocystis spp.'s existing fundamental subniche. In contrast, the greater number of diatoms, correlated with the community trend, within subset H exerted a weaker biological constraint and favored Phaeocystis spp. realized subniche expansion. In conclusion, the results strongly suggest that both abiotic and biotic interactions should be considered to understand Phaeocystis spp. blooms with greater consideration of the preceeding diatoms. HABs needs must therefore be studied as part of the total phytoplankton community.

EarthCARE is the sixth Earth Explorer mission of the European Space Agency's (ESA) Living Planet Program. It is being developed in collaboration with the Japan Aerospace Exploration Agency (JAXA). It has the fundamental objective of improving understanding of the processes involving clouds, aerosols and radiation in the Earth’s atmosphere. The payload of EarthCARE consists of two active and two passive instruments. ESA is developing three of the instruments, an ATmospheric LIDar (ATLID), a Multi-Spectral Imager (MSI) and a Broad-Band Radiometer (BBR). JAXA is developing the Cloud Profiling Radar (CPR). The four instruments will provide co-located data from a single platform, which may be processed individually and in a synergistic manner, to provide a range of products, such as the vertical structure of aerosols and clouds, the corresponding broad-band and narrow-band radiances at the top of the atmosphere, and complementary information for scene identification. ATLID is a backscatter LIDAR, operating at a wavelength of 355 nm, that will record atmospheric echoes from an altitude of 40 km to ground. It incorporates a high resolution spectral filter, which enables the relative separation of aerosol and molecular backscatter. It also measures cross and co-polar components of the Mie backscatter on separate channels. The BBR instrument will make separate measurements of reflected solar radiation and radiated thermal emission from the scene. The MSI instrument will make measurements in seven bands ranging from the visible spectrum, near infrared, short wave infrared, down to thermal infrared, across a 150 km swath. This will aid in scene identification and provide some aerosol information. This paper will provide an overview of the design and function of the instruments and a description of the current progress achieved in their integration and characterization.

International audience; "Au cours d’une transfusion de concentré plaquettaire (CP), le receveur peut manifester un effet indésirable (EIR), dont la gravité est variable. Les EIR peuvent avoir des causes immunologiques de nature inflammatoire. Forts de nos travaux sur l’inflammation et la transfusion, nous avons souhaité nous intéresser toujours aux produits plaquettaires préparés pour transfusion, mais également aux donneurs. Dans le cadre de ce projet, nous étudions le stress des donneurs de sang et son impact sur la composante inflammatoire des concentrés de plaquettes. La première phase de ce projet concerne une enquête sociologique réalisée au sein de l’EFS Auvergne–Rhône-Alpes (Saint-Étienne), dans le cadre d’un travail sur le Stress, Inflammation et Transfusion, qui nous a permis : de mettre en évidence que l’âge des donneurs détermine des comportements différents face au don de sang ; de collecter des données au sein de la maison du don et de distinguer 4 types de donneurs. Ce « profilage » conduit à penser que le stress associé au don est lié aussi à la vie sociale (au travail, à l’avenir, à la famille) ; de relier avant tout le stress du donneur à la peur de l’aiguille et celle de la douleur.Par la suite, l’approche biologique permettra de corréler le ressenti du stress du donneur avec des Biomarqueurs sanguins du stress. Ce projet, à terme, permettra d’identifier les marqueurs plaquettaires qui sont d’un part modulés au cours de la préparation et du stockage des CP et d’autres parts liés au stress du donneur et ainsi envisager la nécessité de mettre en place des actions limitant le stress des donneurs, notamment lors du premier don."

The ATmospheric LIDar (Light Detection and Ranging), ATLID, is part of the payload of the Earth Cloud and Aerosol Explorer (EarthCARE) mission, the sixth Earth Explorer Mission of the European Space Agency (ESA) Living Planet Program. After the successful major step of optical and electrical integration, ATLID has started its performance and functional testing in Toulouse Airbus Defence and Space. The emission part of the instrument has been operated with both TxA (Laser transmitter units) delivered from Leonardo team: as major achievement the main performance of both flight lasers have been tested and confirmed with more than 40mJ UV emission @51Hz with operation via instrument control ACDM flight unit (ATLID control and data management). Tests are parallelized with on one side the EFM test (Electrical Flight Model), and on the other side the OFM tests (Optical flight model). The EFM tests aim at validating the functional and electrical architecture via functional testing on each nominal and redundant path with all the flight electronic units and laser sources. The OFM tests aims validating the receiver alignment from telescope input till fiber detectors, the field of view of the three detection channels and their radiometric performance. OFM vibration tests have been performed and have validated design stability against mechanical loads. End of OFM and EFM tests is planned at summer 2018 and will give go ahead for instrument assembly in its final ATLID PFM configuration with laser cooling system integration. After Ambient performance testing, the environmental test campaign immediately start with EMC, mechanical and thermal vacuum testing.

Since the eighties, several French organizations (Ifremer, CNRS, and marines universities) have joined their forces to operate the first high frequency automated network around France. Now days, 14 Instrumented platforms are in operation along the North Sea, the Atlantic and Mediterranean French coasts. Furthermore, this organization is now largely contributing to the French national Research Infrastructure named "I.R. ILICO".

Direct spectral clustering framework was first proposed to extract general pattern events within multivariate time series. This study investigated the way to identify extreme events, i.e. short duration and/or particular events, with no assumption about their emission date, duration and/or shape. A Multilevel Spectral Clustering (Μ-SC) architecture is proposed and compared with state-of-the-art clustering methods from a simulated manually labeled time series. Due to these promising empirical results, this new deep architecture is applied on marine field data.

Marine waters can be highly heterogeneous both on a spatial and temporal scale, yet monitoring programs currently rely primarily on low-resolution methods. This potentially leads to undersampling. This study explores the potential of two high-resolution methods for monitoring phytoplankton dynamics: fast repetition rate fluorometry for information on phytoplankton photosynthesis and productivity and automated scanning flow cytometry for information on phytoplankton abundance and community composition. These methods were tested in combination with an underway Ferrybox system during four cruises on the Dutch North Sea in April, May, June, and August 2017. The high-resolution methods were able to visualize both the spatial and temporal variability of the phytoplankton community in the Dutch North Sea. Spectral cluster analysis was applied to objectively interpret the multitude of parameters and visualize potential spatial patterns. This resulted in the identification of biogeographic regions with distinct phytoplankton communities, which varied per cruise. Our results clearly show that the sampling based on fixed stations does not give a good representation of the spatial patterns, showing the added value of underway high-resolution measurements. To fully exploit the potential of the tested high-resolution measurement setup, methodological constraints need further research. Among these constraints are accounting for the diurnal cycle in photophysiological parameters concurrent to the spatial variation, better predictions of the electron requirement for carbon fixation to estimate gross primary productivity, and the identification of more flow cytometer clusters with informative value. Nevertheless, the richness of additional information provided by high-resolution methods can improve existing low-resolution monitoring programs towards a more precise and ecosystemic ecological assessment of the phytoplankton community and productivity.