Technicolor (France)

The socio-ecological transition requires not only technological innovation but also new ways of recognizing the social, environmental, and territorial value generated by collective action. Many of these positive externalities remain invisible in conventional assessment frameworks, limiting the legitimacy, financing, and scaling of local sustainability initiatives. This article presents a strategic framework designed to identify and structure positive externalities in collective self-consumption and other transformative projects. The method combines four components: (i) normative identification through the Sustainable Development Goals; (ii) balanced multi-stakeholder participation to surface diverse perspectives; (iii) perceptive mapping using an adapted Kano model; and (iv) strategic articulation. The framework was applied in two contrasting contexts: an energy community centered on shared renewable production, and a women’s empowerment program focused on capability-building and social innovation. These applications do not aim at empirical replication or the validation of results, but at examining how the framework supports collective recognition and strategic structuring in different organizational settings. Across these distinct settings, it led to the formulation of coherent and actionable strategic roadmaps, illustrating how positive externalities can inform governance choices, strengthen institutional legitimacy, and support long-term project consolidation. These results suggest that collective recognition enables externalities to structure strategic action beyond their original sector, demonstrating the potential transferability of the approach. Developed within a research program supported by the French Agency for Ecological Transition (ADEME) and the national urban-transition initiative (PUCA), the framework provides a practical decision architecture for structuring shared value within coordinated strategies.

Inverted perovskite solar cells face performance limitations due to non-radiative recombination at the perovskite surfaces in devices, including functional layers. Advanced characterization and density functional theory reveal that phosphonic acids passivate perovskite surface defects, while piperazinium chloride mitigates interface recombination by improving energy level alignment, introducing a field effect, and homogenizing the surface. Together, the quasi-Fermi level splitting of the perovskite is homogeneously increased by ca. 100 mV. This enables two-terminal perovskite-on-silicon tandems to achieve a certified open-circuit voltage of 2 V for a 1 cm² device and high performance in excess of 31%. The scalability of the passivation is furthermore demonstrated with homogeneously passivated devices reaching certified efficiencies of 28.9% for an active area of 60 cm².

In this paper, we model carrier shutdown in multi-carrier mobile networks as a deep reinforcement learning problem. Our model takes energy-saving actions by turning off carriers and reallocating their users while in addition to maintaining connectivity guarantees a novel user experience metric. Leveraging real and recent datasets, we train and evaluate our model over realistic network scenarios. Our results show more than 15% energy saving with the fulfillment of the user experience constraints, outperforming currently deployed solutions and researched approaches in the literature by almost 50%. More interestingly our approach exhibits generalization properties, a very promising characteristic for its adoption in real mobile networks deployment.

For several years, the metastable helium triplet line has been successfully used as a tracer toprobe atmospheric escape in transiting exoplanets. This absorption in the near-infrared (1083.3 nm) can be observed from the ground using high-resolution spectroscopy, providing new constraints on the mass loss rate and the temperature characterizing the upper atmosphere of close-in exoplanets. This work aims to search for the He triplet signature in fifteen transiting exoplanets, ranging from super-Earths to ultra-hot Jupiters, and observed with SPIRou, a high-resolution (R ∼70 000) near- infrared spectropolarimeter at the CFHT, to bring new constraints or to improve the existing ones regarding atmospheric escape through a homogeneous study. We developed a full data processing and analysis pipeline to correct for the residual telluric and stellar contributions. We then used two different 1D models based on the Parker-wind equations and NLTE radiative transfer to interpret the observational results. We confirm published He triplet detections for HAT-P-11 b, HD 189733 b, and WASP-69 b. We tentatively detect the signature of escaping He in HD 209458 b, GJ 3470 b, and WASP-76 b. We report new constraints on the mass loss rate and temperature for our three detections and set upper limits for the tentative and non-detections. We notably report improved constraints on the mass loss rate and temperature of the escaping gas for TOI-1807 b, and report a non-detection for the debated atmospheric escape in GJ 1214 b. We also conducted the first search for the He signature in GJ 486 b since its discovery and report a non-detection of the He triplet. Finally, we studied the impact of important model assumptions on our retrieved parameters, notably the limitations of 1D models and the influence of the H/He ratio on the derived constraints.

The classical linearly constrained minimum variance (LCMV) beamformer corresponds, in the general case, to the linear, time invariant (TI) and spatio-temporal (ST) complex filter, the output power of which is minimized under some linear constraints. Optimal for stationary signals, this beamformer becomes sub-optimal for (quasi)-cyclostationary observations for which the optimal complex filters are (poly)-periodic (PP) and, under some conditions of widely linear non-circularity. Using these results and the fact that PP filtering is equivalent to FREquency SHifted (FRESH) filtering, the purpose of this paper is to present a first extension of the classical LCMV beamformer, taking into account the potential (quasi)-cyclostationarity and non-circularity properties of the observations. This new cyclic LCMV beamformer is shown to have an equivalent cyclic generalized sidelobe canceller (GSLC) structure. The performance computation of this new cyclic beamformer shows the interest of the latter in cyclostationary contexts and opens a reflection about the optimal constraint choice.

Most of the HO blind source separation methods developed this last decade aim at blindly separating statistically independent sources, assumed stationary and ergodic. Nevertheless, in many situations such as in radiocommunications, the sources are non-stationary and very often (quasi)-cyclostationary (digital modulations). In these contexts, it is important to wonder if the performance of these HO blind source separation methods may be affected by the potential non-stationarity of the sources. The purpose of this paper is to bring some answers to this question through the behaviour analysis of the empirical fourth-order cumulant estimators in the presence of (quasi)-cyclostationary sources.

Subspace techniques have become a popular tool for blind identification of SIMO-FIR systems. A serious drawback of these methods is their sensitivity to the order modeling errors. We show that the so-called approach of subspace methods (which exploits the specular structure of the propagation channel), is robust to channel order overestimation. We propose a deflation procedure to resolve the parametric subspace criterion. Simulations show that this algorithm outperforms classical subspace methods and remain consistent even when the channel order is overestimated by a large factor.

Over the last decade, higher order (HO) methods have been strongly developed in particular to blindly separate instantaneous mixtures of statistically independent stationary sources. However, in many situations of practical interest, the received sources are (quasi)-cyclostationary (digital radiocommunications) and are not always statistically independent but may be correlated to each other, which occurs in particular for HF links or in mobile radiocommunications contexts where propagation multipaths are omnipresent. In such situations, the behaviour of the classical HO blind source separation methods is not known, which may be a limitation to the use of these methods in operational contexts. The purpose of this paper is precisely to fill the gap previously mentioned by analysing the behaviour, in radiocommunications contexts, of three classical HO blind source separation methods when several potentially correlated paths of each source, assumed (quasi)-cyclostationary, are received by the array.

We consider the problem of identifying people on the basis of their walk (gait) pattern. Classical approaches to tackle this problem are based on, e.g., video recordings or piezoelectric sensors embedded in the floor. In this work, we rely on acoustic and vibration measurements, obtained from a microphone and a geophone sensor, respectively. The contribution of this work is twofold. First, we propose a feature extraction method based on an (untrained) shallow scattering network, specially tailored for the gait signals. Second, we demonstrate that fusing the two modalities improves identification in the practically relevant open set scenario.

How does Hardy represent objects in his poetry? What function(s) do they perform? Hardy uses the technique of personification but goes well beyond it. Thus “To a Sea-Cliff” begins as an address to place which finally has everything to do with drama and nothing to do with Nature as such. “The High-School Lawn” and “Green Slates” show Hardy lending objects voice, but the point of the poems lies not in rhetorical technique itself but in broader poetic creation, the recreation of emotion, and the evocation of deep time. Hardy anthropomorphises the animal kingdom in such a way as to suggest that the killing of sentient beings for human consumption, transforming them into “Bags of Meat”, is an ecological tragedy. These poems show the later Hardy as philosophical a poet as ever, an empirical one grounding his poetics, not merely in the object itself, but in what the object points to, and as an analogue for the realia of experience. If this argument were valid, it would add another dimension to the appreciation of Hardy’s thought, complementing the more familiar one highlighting his disillusion. The last poem in the collection, “Why Do I?”, leads us to conclude with a reflection inspired by Tim Ingold’s differentiation between objects and things: the poem is a weird, spectral ars poetica in which the “things” the persona says he “does” are actually, in the absence of any (other) referent, the poems that make up the collection and the activities that form the writing process.