cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
UCSD Field Methods: Todos Santos Cuchumatán Mam
Creators: name: Ramirez, Angela
name: Clem, Emily
name: Jung, Sihun
name: Lim, Jun Jie
name: Mayel, Milad
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2023

description: Recordings of class sessions are organized chronologically. File bundles include sound recordings from a field recorder operated by the language consultant. Where indicated, an additional sound recording output by Zoom is included. ELAN transcription files are included for most recordings. These transcriptions were made at the time of the session and were not subsequently revised. They therefore represent the understanding of the class at the time of the session and involve inconsistencies across the collection reflecting evolving hypotheses.
Modeling the QSO luminosity and spatial clustering at low redshifts
Creators: name: Marulli, F.
name: Crociani, D.
name: Volonteri, M.
name: Branchini, E.
name: Moscardini, L.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the ability of hierarchical models of QSO formation and evolution to match the observed luminosity, number counts and spatial clustering of quasars at redshift z<2. These models assume that the QSO emission is triggered by galaxy mergers, that the mass of the central black hole correlates with halo properties and that quasars shine at their Eddington luminosity except, perhaps, during the very early stages of evolution. We find that models based on simple analytic approximations successfully reproduce the observed B-band QSO luminosity function at all redshifts, provided that some mechanisms is advocated to quench mass accretion within haloes larger than about 1e13 Msun that host bright quasars. These models also match the observed strength of QSO clustering at z~0.8. At larger redshifts, however, they underpredict the QSO biasing which, instead, is correctly reproduced by semi-analytic models in which the halo merger history and associated BHs are followed by Monte Carlo realizations of the merger hierarchy. We show that the disagreement between the luminosity function predicted by semi-analytic models and observations can be ascribed to the use of B-band data, which are a biased tracer of the quasar population, due to obscuration.
description: 13 pages, 9 figures. Accepted by MNRAS
Rigorous Bounds on the Heating Rate in Thue-Morse Quasiperiodically and Randomly Driven Quantum Many-Body Systems
Creators: name: Mori, Takashi
name: Zhao, Hongzheng
name: Mintert, Florian
name: Knolle, Johannes
name: Moessner, Roderich
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The nonequilibrium quantum dynamics of closed many-body systems is a rich yet challenging field. While recent progress for periodically driven (Floquet) systems has yielded a number of rigorous results, our understanding on quantum many-body systems driven by rapidly varying but a- and quasi-periodic driving is still limited. Here, we derive rigorous, non-perturbative, bounds on the heating rate in quantum many-body systems under Thue-Morse quasi-periodic driving and under random multipolar driving, the latter being a tunably randomized variant of the former. In the process, we derive a static effective Hamiltonian that describes the transient prethermal state, including the dynamics of local observables. Our bound for Thue-Morse quasi-periodic driving suggests that the heating time scales like $(ω/g)^{-C\ln(ω/g)}$ with a positive constant $C$ and a typical energy scale $g$ of the Hamiltonian, in agreement with our numerical simulations.
description: 5+6 pages, 2 figures
Definition of iPRODUCE Demonstration Framework
Creators: name: Keller, Jérémy
Publisher: name: Zenodo
Year: 2021

description: Report D2.5 Definition of iPRODUCE demonstration framework is the result of T2.4 Defining the Local Collaborative MDFs, Use-Cases, Innovation Challenges and KPIs. The aim of this task is to provide the identification and general definition of the different Use Cases that will be used as validation scenarios of the iPRODUCE project.
Tecniche di validazione per il Clustering di documenti
Creators: name: Spano, Maria
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2015

description: Classificare i documenti appartenenti ad un determinato corpus, sulla base
del loro contenuto, è uno dei compiti più importanti, se non il più importante,
del Text Mining e dell'Information Retrieval. Quest'obiettivo può essere raggiunto facendo riferimento a tecniche di Classificazione automatica.
Tali tecniche sono comunemente connotate come parte del più ampio contenitore dei metodi di tipo esplorativo, in quanto finalizzati a identificare strutture nei dati non note. La validazione dei risultati viene, quindi, a volte, percepita come un'aggiunta onerosa a quello che viene considerato
un passo iniziale di un processo di conoscenza. Questa percezione
è estremamente pericolosa, perché potrebbe indirizzare gli approfondimenti
successivi in maniera non corretta. Inoltre, i metodi di Classificazione automatica individuano in ogni caso una partizione dei dati, anche quando i dati stessi non presentano alcun raggruppamento naturale.
La motivazione del presente lavoro è, quindi, data dalla consapevolezza dell'importanza di disporre di strumenti di valutazione efficaci, così da fornire
al ricercatore risultati caratterizzati da un certo grado di affidabilità.
Questa tesi pone, quindi, in rassegna la vastissima letteratura relativa agli
strumenti di validazione, ponendo in particolare l'attenzione sulle misure interne per la validazione, poiché rappresentano degli strumenti in grado di fornire un'informazione sintetica della qualità della soluzione ottenuta, valutandola in termini di coesione e separazione dei gruppi ottenuti.
Così come la varietà dei metodi di Clustering discende principalmente dalla
loro applicabilità in molti ambiti diversi, così diverse misure interne di validazione sono state prodotte in diversi contesti. Questa circostanza rende
necessario per i ricercatori avere a disposizione delle linee guida per districarsi
al meglio nelle scelte di uno strumento piuttosto che un altro che possa
risultare più idoneo nei diversi contesti. In questo lavoro si propone un confronto dei punti di forza e dei punti di debolezza di numerosi indici, tra i più utilizzati e più recenti, valutandone la performance su un gran numero di configurazioni. Ne deriva la consapevolezza che la proposta di un nuovo indice sarebbe una operazione di poca efficacia. Si preferisce piuttosto perseguire l'obiettivo di individuare una strategia integrata che metta in relazione i tre elementi dai quali non si può prescindere per eseguire una Cluster Analysis: il tipo di dati, gli algoritmi utilizzati e gli indici di validazione. Questi elementi condizionano in maniera determinante vuoi la qualità dei risultati dell'analisi, vuoi la valutazione che se ne può ottenere.
NGC 4869 in the Coma cluster: twist, wrap, overlap and bend
Creators: name: Lal, Dharam V.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The upgraded Giant Metrewave Radio Telescope (GMRT) has been used to image the head-tail radio galaxy NGC 4869 in the Coma cluster with an angular resolution of 6.26 arcsec at 250-500 MHz and 2.18 arcsec at the 1050-1450 MHz bands. The archival legacy GMRT data have also been used to image the source with angular resolutions from 4.9 to 21.8 arcsec at 610 MHz, 325 MHz, 240 MHz, and 150 MHz. We find that the ~200 kpc scale radio morphology consists of five distinct regions with the clear presence of a pinch at ~1.4 arcmin (= 38.8 kpc) and a ridge at ~3.4 arcmin (= 94.2 kpc) from the head. The sharp bend by ~70 deg at ~3.5 arcmin (= 97 kpc) from the head is possibly due to projection effects. The radio spectra show progressive spectral steepening as a function of distance from the head and there is possibly re-acceleration of the synchrotron electrons and perhaps also magnetic field re-generation in the 6-208 arcsec (= 2.8-96.1 kpc) region of the jet. We report a steep spectrum sheath layer enveloping a flat spectrum spine, hinting at a transverse velocity structure with a fast-moving spine surrounded by a slow-moving sheath layer. We also derive the lifetimes of the radiating electrons and equipartition parameters. A plausible explanation for the characteristic feature, a ridge of emission perpendicular to the direction of tail is the flaring of a straight, collimated radio jet as it crosses a surface brightness edge due to Kelvin-Helmholtz instabilities.
description: 11 pages (here), 8 figures and 2 tables. Figures 1 and 6 are of low quality. Dedicated to the memory of Late Prof. Govind Swarup
Pre-supernova feedback sets the star cluster mass function to a power law and reduces the cluster formation efficiency
Creators: name: Andersson, Eric P.
name: Mac Low, Mordecai-Mark
name: Agertz, Oscar
name: Renaud, Florent
name: Li, Hui
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The star cluster initial mass function is observed to have an inverse power law exponent around 2, yet there is no consensus on what determines this distribution, and why some variation is observed in different galaxies. Furthermore, the cluster formation efficiency covers a range of values, particularly when considering different environments. These clusters are often used to empirically constrain star formation and as fundamental units for stellar feedback models. Detailed galaxy models must therefore accurately capture the basic properties of observed clusters to be considered predictive. We use hydrodynamical simulations of a dwarf galaxy as a laboratory to study star cluster formation. We test different combinations of stellar feedback mechanisms, including stellar winds, ionizing radiation, and supernovae. Each feedback mechanism affects the cluster formation efficiency and cluster mass function. Increasing the feedback budget by combining the different types of feedback decreases the cluster formation efficiency by reducing the number of massive clusters. Ionizing radiation is found to be especially influential. This effect depends on the timing of feedback initiation, as shown by comparing early and late feedback. Early feedback occurs from ionizing radiation and stellar winds with onset immediately after a massive star is formed. Late feedback occurs when energy injection only starts after the main-sequence lifetime of the most massive SN progenitor, a timing that is further influenced by the choice of the most massive SN progenitor. Late feedback alone results in a broad, flat mass function, approaching a log-normal shape in the complete absence of feedback. Early feedback, on the other hand, produces a power-law cluster mass function with lower formation efficiency, albeit with a steeper slope than that usually observed.
description: Submitted to Astronomy & Astrophysics
Investigation of Synthetic Jets Heat Transfer and Flow Field
Creators: name: Greco, Carlo Salvatore
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2015

description: The present thesis deals with the investigation of synthetic jets heat transfer and flow field behaviour. Synthetic jets are devices used mainly for flow control and heat transfer. Such devices are able to "synthetize" a jet from the ambient in which they are embedded through a simple membrane oscillation inside a cavity with an orifice. Such features make them high reliable, silent and easy to be miniaturized. For these reasons, they are widely investigated also as electronic cooling devices. State of art literature shows that the heat transfer performance of these devices are promising. Under these considerations, the present research is focused on the design and analysis of a different type of synthetic jet device with respect to its classical configuration. Such a device is experimentally characterized through the study of its free and impinging flow field. Furthermore the heat transfer rate has been evaluated. The novel configurations are compared to the performance of a classical synthetic jet device.
Floquet engineering of the Lifshitz phase transition in the Hubbard model
Creators: name: Iorsh, I. V.
name: Sedov, D. D.
name: Kolodny, S. A.
name: Sinitskiy, R. E.
name: Kibis, O. V.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Within the Floquet theory of periodically driven quantum systems, we demonstrate that an off-resonant high-frequency electromagnetic field can induce the Lifshitz phase transition in periodical structures described by the one-dimensional repulsive Hubbard model with the nearest and next-nearest-neighbor hopping. The transition changes the topology of electron energy spectrum at the Fermi level, transforming it from the two Fermi points to the four Fermi points, which facilitates the emergence of the superconducting fluctuations in the structure. Possible manifestations of the effect and conditions of its experimental observability are discussed.
description: Published version
Search for physics beyond the standard model in top quark production with additional leptons in the context of effective field theory
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: A search for new physics in top quark production with additional final-state leptons is performed using data collected by the CMS experiment in proton-proton collisions at $\sqrt{s}$ = 13 TeV at the LHC during 2016-2018. The data set corresponds to an integrated luminosity of 138 fb$^{-1}$. Using the framework of effective field theory (EFT), potential new physics effects are parametrized in terms of 26 dimension-six EFT operators. The impacts of EFT operators are incorporated through the event-level reweighting of Monte Carlo simulations, which allows for detector-level predictions. The events are divided into several categories based on lepton multiplicity, total lepton charge, jet multiplicity, and b-tagged jet multiplicity. Kinematic variables corresponding to the transverse momentum ($p_\mathrm{T}$) of the leading pair of leptons and/or jets as well as the $p_\mathrm{T}$ of on-shell Z bosons are used to extract the 95% confidence intervals of the 26 Wilson coefficients corresponding to these EFT operators. No significant deviation with respect to the standard model prediction is found.
description: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/TOP-22-006 (CMS Public Pages)
Scaling approach to related disordered stochastic and free-fermion models
Creators: name: Harris, R. J.
name: Stinchcombe, R. B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Motivated by mapping from a stochastic system with spatially random rates, we consider disordered non-conserving free-fermion systems using a scaling procedure for the equations of motion. This approach demonstrates disorder-induced localization acting in competition with the asymmetric driving. We discuss the resulting implications for the original stochastic system.
description: 11 pages, 14 figures. v2: Minor corrections and slight reorganization
Cooperation and migration for future communication networks
Creators: name: Melito, Fulvio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2015

description: 5G networks will have to address challenges, related to capacity, data rate, latency, connectivity, costs and Quality of Experience (QoE), that LTE-A Long Term Evolution-Advanced) is not able to properly deal with. For this reason, research community is working to identify the set of key technologies that will enable the future mobile network. Three of these technologies fall in the areas of cooperative approaches for wireless networks, Software Defined Networking (SDN), and Network Function Virtualization (NFV). In this thesis work, some original results concerning the aforementioned technologies will be presented, by reserving a greater emphasis to the first one. Specifically, at first, the performance analysis of Multiple-Input Multiple-Output (MIMO) cooperative multiple-relay systems corrupted by Gaussian noise, in the case of naive (non-optimized) approach for the processing at the source and relay nodes, will be presented. Then, the optimal processing design will be faced based on the minimization of the arithmetic mean, over all the substreams, of the symbol error probabilities. At this point, the design of a new equalizer for a Single-Input Single-Output (SISO) Orthogonal-Frequency Division Multiplexing (OFDM) system affected by impulsive noise will be presented and the impact of the joint employment of cooperation and space-time block coding will be shown. At the end, with reference to the migration network primitive, a simplified mathematical model, that unveils the dependence of the total migration time and downtime of the virtual machine memory transfer on the main WAN parameters (such as capacity, buffering, and propagation delay) will be developed.
Spatial-Slepian Transform on the Sphere
Creators: name: Aslam, Adeem
name: Khalid, Zubair
Publisher: name: arXiv
Year: 2020
Subjects: subject: Signal Processing (eess.SP)
subject: Information Theory (cs.IT)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: We present spatial-Slepian transform~(SST) for the representation of signals on the sphere to support localized signal analysis. We use well-optimally concentrated Slepian functions, obtained by solving the Slepian spatial-spectral concentration problem of finding bandlimited and spatially optimally concentrated functions on the sphere, to formulate the proposed transform and obtain the joint spatial-Slepian domain representation of the signal. Due to the optimal energy concentration of the Slepian functions in the spatial domain, the proposed spatial-Slepian transform allows us to probe spatially localized content of the signal. Furthermore, we present an inverse transform to recover the signal from the spatial-Slepian coefficients, and show that well-optimally concentrated rotated Slepian functions form a tight frame on the sphere. We develop an algorithm for the fast computation of the spatial-Slepian transform and carry out computational complexity analysis. We present the formulation of SST for zonal Slepian functions, which are spatially optimally concentrated in the polar cap~(axisymmetric) region, and provide an illustration using the Earth topography map. To demonstrate the utility of the proposed transform, we carry out localized variation analysis; employing SST for detecting hidden localized variations in the signal.
description: 10 pages
La rilevazione dello stato mutazionale di EGFR su campione citologico di neoplasia polmonare a cellule non piccole: il ruolo dell' anatomo patologo nella validazione analitica e clinica.
Creators: name: Bellevicine, Claudio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2015

description: La terapia mirata del carcinoma del polmone non a piccole cellule (NSCLC) con inibitori del dominio tirosin-chinasico (anti-TKI) del recettore del fattore di crescita epidermico (EGFR) è efficace solo nei pazienti con mutazioni di tale gene. Le mutazioni più frequenti  sono rappresentate da delezioni nell'esone 19 e dalla mutazione puntiforme (L858R) nell'esone 21. A causa della scoperta in fase avanzara di tali neoplasie, spesso la diagnosi di carcinoma polmonare è esclusivamente citologica; il DNA estratto dai campioni citologici viene poi utilizzato per determinare lo stato mutazionale di EGFR. Tuttavia, la possibilità che le mutazioni siano distribuite nel tessuto polmonare eterogeneamente è tutt'ora discussa. E' possibile che i campioni citologici non siano del tutto rappresentativi dello stato mutazionale dell'intera neoplasia e quindi, il valore predittivo dell' analisi mutazionale effettuata esclusivamente su citologico è ancora dubbia. Questa Tesi Sperimentale esamina il ruolo del patologo nella gestione del materiale citologico da NSCLC, dalla valutazione pre-analitica del vetrino, alla supervisione delle fasi analitiche dei test molecolari  e, infine, alla sintesi finale nel report diagnostico. È stata inoltre studiata la validità del campione citologico come substrato biologico adeguato nella predizione della risposta alla terapia anti-TKI.
Coupling a single trapped atom to a whispering-gallery-mode microresonator
Creators: name: Will, Elisa
name: Masters, Luke
name: Rauschenbeutel, Arno
name: Scheucher, Michael
name: Volz, Jürgen
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We demonstrate trapping of a single 85Rb atom at a distance of 200 nm from the surface of a whispering-gallery-mode bottle microresonator. The atom is trapped in an optical potential, which is created by retroreflecting a red-detuned focused laser beam from the resonator surface. We counteract the trap-induced light shift of the atomic transition frequency by superposing a second laser beam with suitably chosen power and detuning. This allows us to observe a vacuum Rabi-splitting in the excitation spectrum of the coupled atom-resonator system. This first demonstration of stable and controlled interaction of a single atom with a whispering-gallery-mode in the strong coupling regime opens up the route towards the implementation of quantum protocols and applications that harvest the chiral atom-light coupling present in this class of resonators.
description: 13 pages, 9 figures
Pion Transition Form Factor from Twisted-Mass Lattice QCD and the Hadronic Light-by-Light $π^0$-pole Contribution to the Muon $g-2$
Creators: name: Alexandrou, C.
name: Bacchio, S.
name: Bergner, G.
name: Burri, S.
name: Finkenrath, J.
name: Gasbarro, A.
name: Hadjiyiannakou, K.
name: Jansen, K.
name: Kanwar, G.
name: Kostrzewa, B.
name: Koutsou, G.
name: Ottnad, K.
name: Petschlies, M.
name: Pittler, F.
name: Steffens, F.
name: Urbach, C.
name: Wenger, U.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor $\mathcal{F}_{π^0γγ}(q_1^2,q_2^2)$. Here we present an ab-initio lattice calculation of this quantity in the continuum and at the physical point using twisted-mass lattice QCD. We report our results for the transition form factor parameterized using a model-independent conformal expansion valid for arbitrary space-like kinematics and compare it with experimental measurements of the single-virtual form factor, the two-photon decay width, and the slope parameter. We then use the transition form factors to compute the pion-pole contribution to the hadronic light-by-light scattering in the muon $g-2$, finding $a_μ^{π^0\text{-pole}} = 56.7(3.2) \times 10^{-11}$.
description: 21 pages, 17 figures, 4 tables, updated to published version
CoVR: A Large-Scale Force-Feedback Robotic Interface for Non-Deterministic Scenarios in VR
Creators: name: Bouzbib, Elodie
name: Bailly, Gilles
name: Haliyo, Sinan
name: Frey, Pascal
Publisher: name: arXiv
Year: 2020
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: We present CoVR, a novel robotic interface providing strong kinesthetic feedback (100 N) in a room-scale VR arena. It consists of a physical column mounted on a 2D Cartesian ceiling robot (XY displacements) with the capacity of (1) resisting to body-scaled users' actions such as pushing or leaning; (2) acting on the users by pulling or transporting them as well as (3) carrying multiple potentially heavy objects (up to 80kg) that users can freely manipulate or make interact with each other. We describe its implementation and define a trajectory generation algorithm based on a novel user intention model to support non-deterministic scenarios, where the users are free to interact with any virtual object of interest with no regards to the scenarios' progress. A technical evaluation and a user study demonstrate the feasibility and usability of CoVR, as well as the relevance of whole-body interactions involving strong forces, such as being pulled through or transported.
description: 10 pages (without references), 14 pages total
High Order Asymptotic Expansions of a Good-Bad-Ugly Wave Equation
Creators: name: Duarte, Miguel
name: Feng, Justin
name: Gasperin, Edgar
name: Hilditch, David
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: A heuristic method to find asymptotic solutions to a system of non-linear wave equations near null infinity is proposed. The non-linearities in this model, dubbed good-bad-ugly, are known to mimic the ones present in the Einstein field equations (EFE) and we expect to be able to exploit this method to derive an asymptotic expansion for the metric in General Relativity (GR) close to null infinity that goes beyond first order as performed by Lindblad and Rodnianski for the leading asymptotics. For the good-bad-ugly model, we derive formal expansions in which terms proportional to the logarithm of the radial coordinate appear at every order in the bad field, from the second order onward in the ugly field but never in the good field. The model is generalized to wave operators built from an asymptotically flat metric and it is shown that it admits polyhomogeneous asymptotic solutions. Finally we define stratified null forms, a generalization of standard null forms, which capture the behavior of different types of field, and demonstrate that the addition of such terms to the original system bears no qualitative influence on the type of asymptotic solutions found.
description: 15 pages, 1 figure
Beating resonance patterns and extreme power flux skewing in anisotropic elastic plates
Creators: name: Kiefer, Daniel A.
name: Mezil, Sylvain
name: Prada, Claire
Publisher: name: arXiv
Year: 2023
Subjects: subject: Classical Physics (physics.class-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Elastic waves in anisotropic media can exhibit a power flux that is not collinear with the wave vector. This has notable consequences for waves guided in a plate. Through laser-ultrasonic experiments, we evidence remarkable phenomena due to slow waves in a single crystal silicon wafer. Waves exhibiting power flux orthogonal to their wave vector are identified. A pulsed line source that excites these waves reveals a wave packet radiated parallel to the line. Furthermore, there exist precisely eight plane waves with zero power flux. These so-called zero-group-velocity modes are oriented along the crystal's principal axes. Time acts as a filter in the wave vector domain that selects these modes. Thus, a point source leads to beating resonance patterns with moving nodal curves on the surface of the infinite plate. We observe this pattern as it emerges naturally after a pulsed excitation.
description: 11 pages, 8 figures
Evacuation Dynamics: Empirical Results, Modeling and Applications
Creators: name: Schadschneider, Andreas
name: Klingsch, Wolfram
name: Kluepfel, Hubert
name: Kretz, Tobias
name: Rogsch, Christian
name: Seyfried, Armin
Publisher: name: arXiv
Year: 2008
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: This extensive review was written for the ``Encyclopedia of Complexity and System Science'' (Springer, 2008) and addresses a broad audience ranging from engineers to applied mathematicians, computer scientists and physicists. It provides an extensive overview of various aspects of pedestrian dynamics, focussing on evacuation processes. First the current status of empirical results is critically reviewed as it forms the basis for the calibration of models needed for quantitative predictions. Then various modeling approaches are discussed, focussing on cellular automata models. Finally, some specific applications to safety analysis in public buildings or public transport are presented.
description: 57 pages, 19 figures; to appear in: ``Encyclopedia of Complexity and System Science'', B. Meyers (Ed.) (Springer, Berlin, 2008); for more information and a version with high quality figures, see
Exploring Multifractal Critical Phases in Two-Dimensional Quasiperiodic Systems
Creators: name: Yang, Chao
name: Yang, Weizhe
name: Wang, Yongjian
name: Wang, Yucheng
Publisher: name: arXiv
Year: 2024
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The multifractal critical phase (MCP) fundamentally differs from extended and localized phases, exhibiting delocalized distributions in both position and momentum spaces. The investigation on the MCP has largely focused on one-dimensional quasiperiodic systems. Here, we introduce a two-dimensional (2D) quasiperiodic model with a MCP. We present its phase diagram and investigate the characteristics of the 2D system's MCP in terms of wave packet diffusion and transport based on this model. We further investigate the movement of the phase boundary induced by the introduction of next-nearest-neighbor hopping by calculating the fidelity susceptibility. Finally, we consider how to realize our studied model in superconducting circuits. Our work opens the door to exploring MCP in 2D systems.
description: To appear in Phys. Rev. A
A recursive method for computing zeta functions of varieties
Creators: name: Lauder, Alan G. B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Number Theory (math.NT)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 11Y99; 11G25

description: We present a method for computing the zeta function of a smooth projective variety over a finite field which proceeds by induction on the dimension. We have implemented our approach for some surfaces using the Magma programming language, and present some explicit examples which we have computed.
description: 48 Pages
Wukong: A Scalable and Locality-Enhanced Framework for Serverless Parallel Computing
Creators: name: Carver, Benjamin
name: Zhang, Jingyuan
name: Wang, Ao
name: Anwar, Ali
name: Wu, Panruo
name: Cheng, Yue
Publisher: name: arXiv
Year: 2020
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Serverless computing is increasingly being used for parallel computing, which have traditionally been implemented as stateful applications. Executing complex, burst-parallel, directed acyclic graph (DAG) jobs poses a major challenge for serverless execution frameworks, which will need to rapidly scale and schedule tasks at high throughput, while minimizing data movement across tasks. We demonstrate that, for serverless parallel computations, decentralized scheduling enables scheduling to be distributed across Lambda executors that can schedule tasks in parallel, and brings multiple benefits, including enhanced data locality, reduced network I/Os, automatic resource elasticity, and improved cost effectiveness. We describe the implementation and deployment of our new serverless parallel framework, called Wukong, on AWS Lambda. We show that Wukong achieves near-ideal scalability, executes parallel computation jobs up to 68.17x faster, reduces network I/O by multiple orders of magnitude, and achieves 92.96% tenant-side cost savings compared to numpywren.
description: Appears at ACM Symposium on Cloud Computing (SoCC) 2020
title: Essays on learning and information-processing in financial markets
Creators: name: Risteska, Simona
Publisher: name: London School of Economics and Political Science (LSE)
Year: 2021

description: This dissertation consists of three chapters studying how economic agents learn, form their beliefs and make economically relevant decisions. The main theme of the thesis is to infer beliefs from observable actions and test whether agents process information in a way that is consistent with various theoretical models. In the first chapter I use price data from the real-estate market to infer agent beliefs that are consistent with their pricing behaviour. In particular, I study the way agents make inference from the observable actions of others. In the housing market, where the use of comparables for pricing is most common, I show that the inability to fully grasp the structure of information flows leads agents to overweight stale news due to their repeated use by intermediate agents. The findings are inconsistent with a fully Bayesian model and might instead be reconciled with a model of na¨ıve learning. The second chapter is conjoint work with Francesco Nicolai. We use data on mutual fund portfolio holdings to extract fund managers’ stock return expectations in a fairly general model of portfolio formation. We employ panel regressions to partial out the effect of time-varying stock and manager characteristics and show that subjective expected returns are significantly affected by personal experience. In particular, we provide evidence that professional managers are more strongly influenced by recent returns and those experienced at the early stages of their holding period. The third chapter, co-authored with Francesco Nicolai and Marco Pelosi, provides evidence of the disparity in the incidence of property taxes levied at different points in time. We show that housing demand is significantly less elastic to taxes deferred to the future relative to taxes levied at the moment of purchase, even after accounting for liquidity constraints. We attribute these findings to lack of salience, implying that the burden of deferred taxes will be borne in the future when they are levied. We develop a model to show that the trade-off between lack of salience and liquidity constraints gives rise to an optimal tax mix.
Dasycladales morphogenesis: the pattern formation viewpoint
Creators: name: Dumais, Jacques
Publisher: name: University of British Columbia
Year: 2009

description: The Dasycladalian algae produce diverse whorled structures, among which the best-known are the reproductive whorl (cap) and the vegetative whorls (hair whorls) of Acetabularia acetabulum. The origin of these structures is addressed in terms of three pattern forming mechanisms proposed to explain whorl formation. The mechanisms involve either: mechanical buckling of the cell wall, reaction-diffusion of morphogens along the cell membrane, or Ca²⁺-cytoskeleton mechanochemical interactions in the cytosol. They are described and their idiosyncrasies underlined to provide a ground to test them experimentally. It is also suggested that the closely regulated spacing between the elements of a whorl is a key component of such a test. A detailed staging of whorl formation in the genus Acetabularia shows that the elements constituting the whorl can be traced back to their initiation as localized wall lysis. Stagings of the genera Polyphysa, Batophora, Halicoryne, and Neomeris are also provided. The succession of wall thickening and wall lysis as well as the spacing observed are to some extent incompatible with the idea of wall buckling. The stagings show also the homology between the reproductive and vegetative whorls. Of the different homological systems proposed, one is singled out based on a re-interpretation of the gametophore as a sui generis organ instead of its more common interpretation as a modified hair. Based on this evidence and that provided by the fossil record, it is shown that a reduction of the spacing within a whorl, the addition of one morphogenetic event for the gametophore and a redistribution of growth are sufficient to explain the major differences between the vegetative and reproductive whorls of several genera. More attention is given to the seemingly exceptional case of Halicoryne. A study of membrane-bound and free Ca²⁺ distribution during morphogenesis reveals that Ca²⁺ and growth are in lock step, yet there is no indication that Ca²⁺ would form a prepattern before morphological differentiation, thus providing some evidence that Ca²⁺ is not acting as a morphogen in a Ca²⁺-cytoskeleton morphogenetic mechanism. This discussion of morphogenesis in unicellular algae is shown to be relevant to higher plant morphogenesis given the deep similarities between tip growth and meristematic growth in terms of dynamics and models proposed. I conclude with suggestions for the study of pattern formation and for further research.
Proof-of-concept Quantum Simulator based on Molecular Spin Qudits
Creators: name: Chicco, Simone
name: Allodi, Giuseppe
name: Chiesa, Alessandro
name: Garlatti, Elena
name: Buch, Christian D.
name: Santini, Paolo
name: De Renzi, Roberto
name: Piligkos, Stergios
name: Carretta, Stefano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The use of $d$-level qudits instead of two-level qubits can largely increase the power of quantum logic for many applications, ranging from quantum simulations to quantum error correction. Molecular Nanomagnets are ideal spin systems to realize these large-dimensional qudits. Indeed, their Hamiltonian can be engineered to an unparalleled extent and can yield a spectrum with many low-energy states. In particular, in the last decade intense theoretical, experimental and synthesis efforts have been devoted to develop quantum simulators based on Molecular Nanomagnets. However, this remarkable potential is practically unexpressed, because no quantum simulation has ever been experimentally demonstrated with these systems. Here we show the first prototype quantum simulator based on an ensemble of molecular qudits and a radiofrequency broadband spectrometer. To demonstrate the operativity of the device, we have simulated quantum tunneling of the magnetization and the transverse-field Ising model, representative of two different classes of problems. These results represent an important step towards the actual use of molecular spin qudits in quantum technologies.
Masked corroborees of the northwest - "stand up in my head"
Creators: name: Sweeney, Dominique
Publisher: name: Canberra, ACT : The Australian National University
Year: 2009
Subjects: subject: DU124.R57 S94 2009
subject: Masks Symbolic aspects Australia, Northern
subject: Dance, Aboriginal Australian Australia, Northern
subject: Aboriginal Australians Rites and ceremoniesAustralia, Northern
subject: Aboriginal Australians Folklore
subject: Australia, Northern

description: In northwest Australia a range of corroborees incorporate the use of masks. These and other performance objects connect bodies to country, cultural knowledge and ancestors. They also reaffirm the political status of people in their country. My thesis is in two parts: making a digital video (DV) about the way these masks come into being and how they are used; and this written thesis analysing the groundwork process involved in making the DV. The Ngarinyin, Narinyman and Worla people of northwest Australia are peoples with whom I have concentrated my research and video documentation concerning the animation of Wunggurr (Rainbow Serpent) and Ngarranggarni, the cosmological entirety, through performance. Masking in these corroborees is a process of manifestation when the boundary between the body of a performer and the landscape/cosmos/ancestor become one. Performances elicit questions about relationships to country, cultural knowledge, and with the dead. Do performances mean the same when performed away from their country of origin at national and international festivals? Are the conceptual categories 'performance' and 'mask' sufficient to describe what is happening in these circumstances? What are the implications for Performance Studies in looking more deeply into these performances? It is through my growing understanding and representation of the contemporary circumstances surrounding the people involved in the creation and preparation of corroborees, that this thesis explores.
Sample-efficient estimation of entanglement entropy through supervised learning
Creators: name: Rieger, Maximilian
name: Reh, Moritz
name: Gärttner, Martin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We explore a supervised machine learning approach to estimate the entanglement entropy of multi-qubit systems from few experimental samples. We put a particular focus on estimating both aleatoric and epistemic uncertainty of the network's estimate and benchmark against the best known conventional estimation algorithms. For states that are contained in the training distribution, we observe convergence in a regime of sample sizes in which the baseline method fails to give correct estimates, while extrapolation only seems possible for regions close to the training regime. As a further application of our method, highly relevant for quantum simulation experiments, we estimate the quantum mutual information for non-unitary evolution by training our model on different noise strengths.
description: 6 pages, 4 figures
Machine listening in a neonatal intensive care unit
Creators: name: Tailleur, Modan
name: Lostanlen, Vincent
name: Rivière, Jean-Philippe
name: Aumond, Pierre
Publisher: name: arXiv
Year: 2024
Subjects: subject: Sound (cs.SD)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Audio and Speech Processing (eess.AS)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Oxygenators, alarm devices, and footsteps are some of the most common sound sources in a hospital. Detecting them has scientific value for environmental psychology but comes with challenges of its own: namely, privacy preservation and limited labeled data. In this paper, we address these two challenges via a combination of edge computing and cloud computing. For privacy preservation, we have designed an acoustic sensor which computes third-octave spectrograms on the fly instead of recording audio waveforms. For sample-efficient machine learning, we have repurposed a pretrained audio neural network (PANN) via spectral transcoding and label space adaptation. A small-scale study in a neonatological intensive care unit (NICU) confirms that the time series of detected events align with another modality of measurement: i.e., electronic badges for parents and healthcare professionals. Hence, this paper demonstrates the feasibility of polyphonic machine listening in a hospital ward while guaranteeing privacy by design.
Emotional EEG Classification using Connectivity Features and Convolutional Neural Networks
Creators: name: Moon, Seong-Eun
name: Chen, Chun-Jui
name: Hsieh, Cho-Jui
name: Wang, Jane-Ling
name: Lee, Jong-Seok
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Convolutional neural networks (CNNs) are widely used to recognize the user's state through electroencephalography (EEG) signals. In the previous studies, the EEG signals are usually fed into the CNNs in the form of high-dimensional raw data. However, this approach makes it difficult to exploit the brain connectivity information that can be effective in describing the functional brain network and estimating the perceptual state of the user. We introduce a new classification system that utilizes brain connectivity with a CNN and validate its effectiveness via the emotional video classification by using three different types of connectivity measures. Furthermore, two data-driven methods to construct the connectivity matrix are proposed to maximize classification performance. Further analysis reveals that the level of concentration of the brain connectivity related to the emotional property of the target video is correlated with classification performance.
Interloper treatment in dynamical modelling of galaxy clusters
Creators: name: Wojtak, Radoslaw
name: Lokas, Ewa L.
name: Mamon, Gary A.
name: Gottloeber, Stefan
name: Prada, Francisco
name: Moles, Mariano
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The aim of this paper is to study the efficiency of different approaches to interloper treatment in dynamical modelling of galaxy clusters. Using cosmological N-body simulation of standard LCDM model, we select 10 massive dark matter haloes and use their particles to emulate mock kinematic data in terms of projected galaxy positions and velocities as they would be measured by a distant observer. Taking advantage of the full 3D information available from the simulation, we select samples of interlopers defined with different criteria. The interlopers thus selected provide means to assess the efficiency of different interloper removal schemes found in the literature. We study direct methods of interloper removal based on dynamical or statistical restrictions imposed on ranges of positions and velocities available to cluster members. In determining these ranges, we use either the velocity dispersion criterion or a maximum velocity profile. We also generalize the common approaches taking into account both the position and velocity information. Another criterion is based on the dependence of the commonly used virial mass and projected mass estimators on the presence of interlopers. We find that the direct methods exclude on average 60-70 percent of unbound particles producing a sample with contamination as low as 2-4 percent. Next, we consider indirect methods of interloper treatment which are applied to the data stacked from many objects. In these approaches, interlopers are treated in a statistical way as a uniform background which modifies the distribution of cluster members. Using a Bayesian approach, we reproduce the properties of composite clusters and estimate the probability of finding an interloper as a function of distance from the object centre.
description: 15 pages, 14 figures, final version accepted for publication in A&A