École Polytechnique Fédérale de Lausanne
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Observation of ᴧ<inf>b</inf><sup>0</sup>→ ᴧ<inf>c</inf><sup>+</sup> D̄<sup>(*)0</sup>K<sup>−</sup> and ᴧ<inf>b</inf><sup>0</sup>→ ᴧ<inf>c</inf><sup>+</sup> D<inf>s</inf><sup>*−</sup> decays
No full textThe decays Λb 0→Λc +D¯(∗)0K- and Λb 0→Λc +Ds ∗- are observed for the first time, in proton-proton collision data at s=13TeV, corresponding to an integrated luminosity of 5.4fb-1 collected with the LHCb detector. Their ratios of branching fractions with respect to the Λb 0→Λc +Ds - mode are measured to be (Formula presented.) where the first uncertainties are statistical, the second systematic, and the third, for the Λb 0→Λc +D¯(∗)0K- decays, are due to the uncertainties on the branching fractions of the Ds -→K-K+π- and D¯0→K+π- decay modes. The measured branching fractions probe factorization assumptions in effective theories and provide the normalization for future pentaquark searches in Λb 0→Λc +D¯(∗)0K- decay channels.LPHE-OSPH-SBLPHE-RMLPHE-L
Harmonic Stability Analysis of Microgrids with Converter-Interfaced Distributed Energy Resources, Part II: Case Studies
No full textIn Part I of this paper a method for the Harmonic Stability Assessment (HSA) of power systems with a high share of Converter-Interfaced Distributed Energy Resources (CIDERs) was proposed. Specifically, the Harmonic State-Space (HSS) model of a generic power system is derived through combination of the components’ HSS models. The HSS models of CIDERs and grid are based on Linear Time-Periodic (LTP) models, capable of representing the coupling between different harmonics. In Part II, the HSA of a grid-forming, and two grid-following CIDERs (i.e., ex-and including the DC-side modelling) is performed. More precisely, the classification of the eigenvalues, the impact of the maximum harmonic order on the locations of the eigenvalues, and the sensitivity curves of the eigenvalues w.r.t. to control parameters are provided. These analyses allow to study the physical meaning and origin of the CIDERs’ eigenvalues. Additionally, the HSA is performed for a representative example system derived from the CIGR’E low-voltage benchmark system. A case of harmonic instability is identified through the system eigenvalues, and validated with Time-Domain Simulations (TDS) in Simulink. It is demonstrated that, as opposed to stability analyses based on Linear Time-Invariant (LTI) models, the HSA is suitable for the detection of harmonic instability.DES
Electroanalytical applications of ITIES – A review
No full textOver the last decades, the interface between two immiscible electrolyte solutions (ITIES) attracted considerable attention of the scientific community due to their vast applications, such as extraction, catalysis, partition studies and sensing. The aim of this Review is to highlight the potential of electrochemistry at the ITIES for analytical purposes, focusing on ITIES-based sensors for detection and quantification of chemically and biologically relevant (bio)molecules. We start by addressing the evolution of ITIES in terms of number of publications over the years along with an overview of their main applications (Chapter 1). Then, we provide a general historical perspective about pioneer voltammetric studies at water/oil systems (Chapter 2). After that, we discuss the most impacting improvements on ITIES sensing systems from both perspectives, set-up design (interface stabilization and miniaturization, selection of the organic solvent, etc.) and optimization of experimental conditions to improve selectivity and sensitivity (Chapter 3). In Chapter 4, we discuss the analytical applications of ITIES for electrochemical sensing of several types of analytes, including drugs, pesticides, proteins, among others. Finally, we highlight the present achievements of ITIES as analytical tool and provide future challenges and perspectives for this technology (Chapter 5).ISIC-DI
Exploring Masked Autoencoders for Sensor-Agnostic Image Retrieval in Remote Sensing
No full textSelf-supervised learning through masked autoencoders (MAEs) has recently attracted great attention for remote sensing (RS) image representation learning, and thus embodies a significant potential for content-based image retrieval (CBIR) from ever-growing RS image archives. However, the existing MAE based CBIR studies in RS assume that the considered RS images are acquired by a single image sensor, and thus are only suitable for uni-modal CBIR problems. The effectiveness of MAEs for cross-sensor CBIR, which aims to search semantically similar images across different image modalities, has not been explored yet. In this paper, we take the first step to explore the effectiveness of MAEs for sensor-agnostic CBIR in RS. To this end, we present a systematic overview on the possible adaptations of the vanilla MAE to exploit masked image modeling on multi-sensor RS image archives (denoted as cross-sensor masked autoencoders [CSMAEs]) in the context of CBIR. Based on different adjustments applied to the vanilla MAE, we introduce different CSMAE models. We also provide an extensive experimental analysis of these CSMAE models. We finally derive a guideline to exploit masked image modeling for uni-modal and cross-modal CBIR problems in RS. The code of this work is publicly available at https://github.com/jakhac/CSMAE.ECE
MALDI-TOF Mass Fingerprinting for Rapid Identification of Bacteria: Experimental Procedures
No full textISIC-DI
Area-Oriented Resubstitution For Networks of Look-Up Tables
No full textThis paper addresses the challenge of reducing the number of nodes in Look-Up Table (LUT) networks with two significant applications. First, Field-Programmable Gate Arrays (FPGAs) can be modelled as networks of LUTs, and minimizing the node count is imperative to meet resource constraints. Second, in area-oriented design space exploration for standard-cell designs, collapsing a circuit into a LUT network, restructuring it, and later remapping to the original representation helps escape local minima. Thus, the development of algorithms for optimizing and restructuring LUT networks holds considerable promise for area-oriented optimization. Substitution (also called resubstitution) is a powerful logic minimization method that can identify non-local logic dependencies and exploit them for logic minimization. State-of-the-art substitution algorithms for LUT networks rely heavily on SAT solving, limiting the number of optimization attempts and the size of the substitution sub-networks to one node mishchenko2011scalable. Conversely, our method relies on circuit simulation to increase the number of substitution candidates and enables substitutions with more than one node. The experimental results show that the proposed method identifies optimization opportunities overlooked by other methods, improving 11 out of 23 best-known results in the EPFL synthesis competition and yielding a 3.46% area reduction compared to the state-of-the-art.LSI
Observation of New Charmonium or Charmoniumlike States in B+ →D∗±D∓K+ Decays
No full textA study of resonant structures in B+→D∗+D-K+ and B+→D∗-D+K+ decays is performed, using proton-proton collision data at center-of-mass energies of s=7, 8, and 13 TeV recorded by the LHCb experiment, corresponding to an integrated luminosity of 9 fb-1. A simultaneous amplitude fit is performed to the two channels with contributions from resonances decaying to D∗-D+ and D∗+D- states linked by C parity. This procedure allows the C parities of resonances in the D∗±D∓ mass spectra to be determined. Four charmonium or charmoniumlike states are observed decaying into D∗±D∓: ηc(3945), hc(4000), χc1(4010), and hc(4300), with quantum numbers JPC equal to 0-+, 1+-, 1++, and 1+-, respectively. At least three of these states have not been observed previously. In addition, the existence of the Tc¯s¯0∗(2870)0 and Tc¯s¯1∗(2900)0 resonances in the D-K+ mass spectrum, already observed in the B+→D+D-K+ decay, is confirmed in a different production channel.LPHE-OSPH-SBLPHE-RMLPHE-L
Le haut, le bas, et l’entre-deux
No full textAt the eastern end of the Flon platform stands a building unnoticed by passersby. Initially a garage, the building currently hosting the Parking Saint-François was built in 1957, replacing the former freight station with a brand new one dedicated to the transport of people. Now standing on a public transport node, connecting the upper city and the lower city through a series of elevators and footbridges, the building still carries the late 60s’ ambition to attract cars always deeper into city centres. Over the next decade, the surroundings of the Parking Saint-François are bound to undergo important changes, further increasing its connectivity in terms of public transports and its importance as a throughway. Thus questioning the pertinence of the building’s current program and providing the opportunity for an adaptation to the evolving neighbourhood life. Le haut, le bas, et l’entre-deux is thought of as a reaction to these changes. The project’s priority is to consider the building’s inherent narrative and existing infrastructures as a starting point for the injection of a new public use, answering to the lack of non-commercial activities of the surroundings. By subtracting where light is needed, connecting where flow is interrupted and inserting where programm requires it, the building becomes an extension of the neighbouring contexts and allows for their mixing. Cyclists and pedestrians now flow where cars used to. The comic book library, cantina and sports fields are organised around the circulation, where boundaries are blurred, creating new interactions between people passing by or coming for.EAST-COENAC-SARCote: 2024.035MEM.1/1Groupe de suivi: Fröhlich, Anja (dir. pédagogique) ; Graezer Bideau, Florence (prof.) ; Borges, Tiago (maître EPFL) ; Szacka, Léa-Catherine (expert)Professeur responsable de l'Enoncé: Graezer Bideau, Florence (EPFL CDH-DIR)Enoncé théorique de master: Coloured Considerations. Towards a tangible reading of facade colours in two of Lausanne's constellation
Aryl-Acetylene Layered Hybrid Perovskites in Photovoltaics
No full textMetal halide perovskites have shown exceptional potential in converting solar energy to electric power in photovoltaics, yet their application is hampered by limited operational stability. This stimulated the development of hybrid layered (two-dimensional, 2D) halide perovskites based on hydrophobic organic spacers, templating perovskite slabs, as a more stable alternative. However, conventional organic spacer cations are electronically insulating, resulting in charge confinement within the inorganic slabs, thus limiting their functionality. This can be ameliorated by extending the pi-conjugation of the spacer cations. We demonstrate the capacity to access Ruddlesden-Popper and Dion-Jacobson 2D perovskites incorporating for the first time aryl-acetylene-based (4-ethynylphenyl)methylammonium (BMAA) and buta-1,3-diyne-1,4-diylbis(4,1-phenylene)dimethylammonium (BDAA) spacers, respectively. We assess their unique opto(electro)ionic characteristics by a combination of techniques and apply them in mixed-dimensional perovskite solar cells that show superior device performances with a power conversion efficiency of up to 23 % and higher operational stability, opening the way for multifunctionality in layered hybrid materials and their application.LPILCBCPV-LA
Poïesis Industrielle Reconversion de l’ancienne papeterie du Vallon du Groseau en un centre de production théâtrale
No full textComposant un site industriel emblématique du Vaucluse, département provençal, abandonné depuis sa fermeture en 2009, les anciennes papeteries de Malaucène ont trouvé un nouveau propriétaire : la Fabrique du Ventoux. L’objectif de cette société coopérative d’intérêt collectif est de permettre aux habitants de Malaucène de se réapproprier ce lieu ancré dans les mémoires locales. L’ancienne usine du Vabre, en contrebas, accueillera des logements sociaux, une zone artisanale ainsi que des installations sportives. En amont, l’usine abandonnée du Groseau, sur laquelle porte ce projet de réhabilitation, deviendra un centre de production théâtrale. Elle sera liée au site naturel du Vallon notamment à travers sa source, tout en participant au rayonnement culturel d’Avignon et à son festival international de théâtre. Situé sur le tracé du GR91 et du sentier pédestre le long de la rivière du Groseau, le site devient également un point d’étape pour les randonneurs et les Malaucéniens se rendant à la source. Orienté par une recherche théorique sur le thème du confort et de l’élargissement possible des commodités dans la gestion climatique, le projet tire profit du contexte naturel, social et bâti pour gérer son climat intérieur, en minimisant les intrants technologiques. L’eau combinée à la ventilation naturelle assure le rafraîchissement nécessaire en été. L’énergie du soleil, le potentiel thermique de la chaleur générée par le corps et le chauffage ciblé par conduction assurent le confort d’hiver.LIFENAC-SARCote: 2024.026MEM.1/1Groupe de suivi: Taillieu, Jo François (dir. pédagogique) ; Lapierre, Eric (prof.) ; Pretolani, Mattia (maître EPFL) ; Eliasson, Susanne (expert)Professeur responsable de l'Enoncé: Taillieu, Jo François (ENAC IA LIF)Enoncé théorique de master: alterconfort: élargir le spectre des commodité