cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
One hundred second bit-flip time in a two-photon dissipative oscillator
Creators: name: Berdou, C.
name: Murani, A.
name: Reglade, U.
name: Smith, W. C.
name: Villiers, M.
name: Palomo, J.
name: Rosticher, M.
name: Denis, A.
name: Morfin, P.
name: Delbecq, M.
name: Kontos, T.
name: Pankratova, N.
name: Rautschke, F.
name: Peronnin, T.
name: Sellem, L. -A.
name: Rouchon, P.
name: Sarlette, A.
name: Mirrahimi, M.
name: Campagne-Ibarcq, P.
name: Jezouin, S.
name: Lescanne, R.
name: Leghtas, Z.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Current implementations of quantum bits (qubits) continue to undergo too many errors to be scaled into useful quantum machines. An emerging strategy is to encode quantum information in the two meta-stable pointer states of an oscillator exchanging pairs of photons with its environment, a mechanism shown to provide stability without inducing decoherence. Adding photons in these states increases their separation, and macroscopic bit-flip times are expected even for a handful of photons, a range suitable to implement a qubit. However, previous experimental realizations have saturated in the millisecond range. In this work, we aim for the maximum bit-flip time we could achieve in a two-photon dissipative oscillator. To this end, we design a Josephson circuit in a regime that circumvents all suspected dynamical instabilities, and employ a minimally invasive fluorescence detection tool, at the cost of a two-photon exchange rate dominated by single-photon loss. We attain bit-flip times of the order of 100 seconds for states pinned by two-photon dissipation and containing about 40 photons. This experiment lays a solid foundation from which the two-photon exchange rate can be gradually increased, thus gaining access to the preparation and measurement of quantum superposition states, and pursuing the route towards a logical qubit with built-in bit-flip protection.
Measurements of Higgs boson production in the decay channel with a pair of $τ$ leptons in proton-proton collisions at $\sqrt{s}$ = 13 TeV
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Measurements of Higgs boson production, where the Higgs boson decays into a pair of $τ$ leptons, are presented, using a sample of proton-proton collisions collected with the CMS experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. Three analyses are presented. Two are targeting Higgs boson production via gluon fusion and vector boson fusion: a neural network based analysis and an analysis based on an event categorization optimized on the ratio of signal over background events. These are complemented by an analysis targeting vector boson associated Higgs boson production. Results are presented in the form of signal strengths relative to the standard model predictions and products of cross sections and branching fraction to $τ$ leptons, in up to 16 different kinematic regions. For the simultaneous measurements of the neural network based analysis and the analysis targeting vector boson associated Higgs boson production signal strengths are found to be 0.82 $\pm$ 0.11 for inclusive Higgs boson production, 0.67 $\pm$ 0.19 (0.81 $\pm$ 0.17) for the production mainly via gluon fusion (vector boson fusion), and 1.79 $\pm$ 0.45 for vector boson associated Higgs boson production.
description: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables, including additional supplementary figures and tables, can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-19-010 (CMS Public Pages)
Systematic Analysis of Double-Beta Decay Half Lives
Creators: name: Pritychenko, B.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Evaluated $2β^{-}(2ν)$ half-lives and their systematics were reexamined in the framework of a phenomenological approach. Decay rate dependence on nuclear deformation, decay energy, shape coexistence, and forbidden transitions was observed. The following analysis showed distinct impacts of decay energy on half-lives and deformation parameters on effective nuclear matrix elements. These findings were used to predict $T_{1/2}$ for 36 isotopes of interest. Present work results were compared with published data.
description: 14 pages, 3 figures
Correlated Insulator Collapse due to Quantum Avalanche via In-Gap Ladder States
Creators: name: Han, Jong E.
name: Aron, Camille
name: Han, Jae-Ho
name: Kim, Ki-Seok
name: Mansaray, Ishiaka
name: Randle, Michael
name: Bird, Jonathan P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We propose a microscopic mechanism to resolve the long-standing puzzle of the insulator-to-metal transition in correlated electronic systems, most notably charge-density-wave (CDW) materials and Mott insulators, driven far-from-equilibrium by a DC electric field. By introducing a generic model of electrons coupled to an inelastic medium of phonons, we demonstrate that an electron avalanche can occur in the bulk limit of such insulators at arbitrarily small electric field. The quantum avalanche arises by the generation of a ladder of in-gap states, created by a multi-phonon emission process. Hot-phonons in the avalanche trigger a premature and partial collapse of the correlated gap. The details of the phonon spectrum dictate two-stage versus single-stage mechanisms which we associate with CDW and Mott resistive transitions, respectively. The electron and phonon temperatures, as well as the temperature dependence of the threshold fields, point to the quantum nature of this nonequilibrium phase transition.
(Anti)evaporation of Dyonic Black Holes in string-inspired dilaton $f(R)$-gravity
Creators: name: Addazi, Andrea
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss dyonic black hole solutions in the case of $f(R)$-gravity coupled with a dilaton and two gauge bosons. The study of such a model is highly motivated from string theory. Our Black Hole solutions are extensions of the one firstly studied by Kallosh, Linde, Ortín, Peet and Van Proyen (KLOPV) in [arXiv:hep-th/9205027]. We will show that extreme solutions are unstable. In particular, these solutions have Bousso-Hawking-Nojiri-Odintsov (anti)evaporation instabilities.
title: A Clumsy Encounter: The dyspraxic ideal meets drawing from observation as an official and discriminatory discourse
Creators: name: Penketh, Claire
Publisher: name: Goldsmiths, University of London
Year: 2010

description: Drawing from observation is a form of practice employed in art and design secondary education in the UK. It is positioned within a pedagogical concept of art education that combines particular forms of representation with the development of skill and technical accomplishment. This study engages with the 'voices' of four 'dyspraxic' participants whose experiences of art education sit within this context. Dyspraxia, alternatively referred to as Developmental Coordination Disorder (DCD), is a term that identifies difficulties with the development of physical coordination related to sensory processing. However, it could be argued that factors used in determining whether a child is identified as dyspraxic are subject to complex social, cultural and more specifically educational contexts. This study focuses on the way in which drawing from direct observation is experienced by pupils as part of their art and design education and these experiences are viewed through a 'dyspraxic lens' in order to sharpen the focus on technical skill and accomplishment in producing representations through drawing. It offers a critique of the creation of the dyspraxic subject and drawing from observation by exploring the point at which the' dyspraxic ideal' derived from, or created by, the literature intersects with participants' experiences of compulsory art education. This is an interrogation of the complexity of observational drawing as a specific practice not within a closed community of art education but within the social and cultural domain of other critical debates within education, specifically those related to inclusion. The complexity of these sites is explored here and approaches that seek to rationalise and compartmentalise educational experience are challenged and disrupted.
A hybridizable discontinuous Galerkin method for the fully coupled time-dependent Stokes/Darcy-transport problem
Creators: name: Cesmelioglu, Aycil
name: Pham, Dinh Dong
name: Rhebergen, Sander
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: We present a high-order hybridized discontinuous Galerkin (HDG) method for the fully coupled time-dependent Stokes-Darcy-transport problem where the fluid viscosity and source/sink terms depend on the concentration and the dispersion/diffusion tensor depends on the fluid velocity. This HDG method is such that the discrete flow equations are compatible with the discrete transport equation. Furthermore, the HDG method guarantees strong mass conservation in the $H^{\rm div}$ sense and naturally treats the interface conditions between the Stokes and Darcy regions via facet variables. We employ a linearizing decoupling strategy where the Stokes/Darcy and the transport equations are solved sequentially by time-lagging the concentration. We prove well-posedness and optimal a priori error estimates for the velocity and the concentration in the energy norm. We present numerical examples that respect compatibility of the flow and transport discretizations and demonstrate that the discrete solution is robust with respect to the problem parameters.
description: 38 pages, 5 figures
Averaging theory at any order for computing limit cycles of discontinuous piecewise differential systems with many zones
Creators: name: Llibre, Jaume
name: Novaes, Douglas D.
name: Rodrigues, Camila A. B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 34C29, 34C25, 37G15, 34C07

description: This work is devoted to study the existence of periodic solutions for a family of discontinuous differential systems $Z(x,y;ε)$ with many zones. We show that for $ε$ sufficiently small the averaged functions at any order control the existence of crossing limit cycles for systems in this family. We also provide some examples dealing with nonlinear centers.
Vibration and jitter of free-flowing thin liquid sheets as target for high-repetition-rate laser-ion acceleration
Creators: name: Cao, Zhengxuan
name: Peng, Ziyang
name: Shou, Yinren
name: Zhao, Jiarui
name: Chen, Shiyou
name: Gao, Ying
name: Liu, Jianbo
name: Wang, Pengjie
name: Mei, Zhusong
name: Pan, Zhuo
name: Kong, Defeng
name: Qi, Guijun
name: Xu, Shirui
name: Liu, Zhipeng
name: Liang, Yulan
name: Xu, Shengxuan
name: Song, Tan
name: Chen, Xun
name: Wu, Qingfan
name: Liu, Xuan
name: Ma, Wenjun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Very thin free-flowing liquid sheets are promising targets for high-repetition-rate laser-ion acceleration. In this work, we report the generation of micrometer-thin free-flowing liquid sheets from the collision of two liquid jets, and study the vibration and jitter in their surface normal direction. The dependence of their motion amplitudes on the generation parameters is studied in detail. The origins of the vibration and jitter are discussed. Our results indicate that when the generation parameters are optimized, the motion amplitudes in the stable region can be stabilized below 3.7 μm to meet the stringent requirement of sheet position stability for a tight-focusing setup in laser-ion acceleration experiments.
description: 13 pages, 5 figures, Original Reasearch
Characterisation of red supergiants in the Gaia spectral range
Creators: name: Dorda, Ricardo
name: González-Fernández, Carlos
name: Negueruela, Ignacio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The infrared Calcium Triplet and its nearby spectral region have been used for spectral and luminosity classification of late-type stars, but the samples of cool supergiants (CSGs) used have been very limited (in size, metallicity range, and spectral types covered). The spectral range of the Gaia Radial Velocity Spectrograph (RVS) covers most of this region but does not reach the main TiO bands in this region, whose depths define the M sequence. We study the behaviour of spectral features around the Calcium Triplet and develop effective criteria to identify and classify CSGs, comparing their efficiency with other methods previously proposed. We measure the main spectral features in a large sample (almost 600) of CSGs from three different galaxies, and we analyse their behaviour through a principal component analysis. Using the principal components, we develop an automatised method to differentiate CSGs from other bright late-type stars, and to classify them. The proposed method identifies a high fraction of the supergiants (SGs) in our test sample, which cover a wide metallicity range (SGs from the SMC, the LMC, and the Milky Way) and with spectral types from G0 up to late-M. In addition, it is capable to separate most of the non-SGs in the sample, identifying as SGs only a very small fraction of them. A comparison of this method with other previously proposed shows that it is more efficient and selects less interlopers. A way to automatically assign a spectral type to the SGs is also developed. We apply this study to spectra at the resolution and spectral range of the Gaia RVS, with a similar success rate. The method developed identifies and classifies CSGs in large samples, with high efficiency and low contamination, even in conditions of wide metallicity and spectral-type ranges.
description: Accepted for publication in A&A
Some long-run comparative-static effects under imperfect competition : a mesoeconomic approach
Creators: name: Zhou., Ying
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Single-particle spectroscopic strength from nucleon transfer reactions with a three-nucleon force contribution
Creators: name: Timofeyuk, N. K.
name: Moschini, L.
name: Gómez-Ramos, M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The direct reaction theory widely used to study single-particle spectroscopic strength in nucleon transfer experiments is based on a Hamiltonian with two-nucleon interactions only. We point out that in reactions with a loosely-bound projectile, where clustering and breakup effects are important, an additional three-body force arises due to three-nucleon ($3N$) interaction between two nucleons belonging to different clusters in the projectile and a target nucleon. We study the effects of this force on nucleon transfer in $(d,p)$ and $(d,n)$ reactions on $^{56}$Ni, $^{48}$Ca, $^{26m}$Al and $^{24}$O targets at deuteron incident energies between 4 and 40 MeV/nucleon. Deuteron breakup is treated exactly within a continuum discretized coupled-channel approach. It was found that an additional three-body force can noticeably alter the angular distributions at forward angles, with consequences for spectroscopic factors' studies. Additional study of transfer to $2p$ continuum in the $^{25}$F$(p,2p)^{24}$O reaction, involving the same overlap function as in the $^{24}$O($d,n)^{25}$F case, revealed that $3N$ force affects the $(d,n)$ and $(p,2p)$ reactions in a similar way, increasing the cross sections and decreasing spectroscopic factors, although its influence at the main peak of $(p,2p)$ is weaker. The angle-integrated cross sections are found to be less sensitive to the 3N force contribution, they increase by less than 20$\%$. Including 3N interactions in nucleon removal reactions makes an essential step towards bringing together nuclear structure theory, where 3N force is routinely used, and nuclear direct reaction theory, based on two-nucleon interactions only.
description: Accepted in Physics Letters B
Ultrafast collapse of molecular polaritons in photoswitch-nanoantennas at room temperature
Creators: name: Kuttruff, Joel
name: Romanelli, Marco
name: Pedrueza-Villalmanzo, Esteban
name: Allerbeck, Jonas
name: Fregoni, Jacopo
name: Saavedra-Becerril, Valeria
name: Andréasson, Joakim
name: Brida, Daniele
name: Dmitriev, Alexandre
name: Corni, Stefano
name: Maccaferri, Nicolò
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Molecular polaritons are hybrid light-matter states that emerge when a molecular transition strongly interacts with photons in a resonator. At optical frequencies, this interaction unlocks a way to explore and control new chemical phenomena at the nanoscale. Achieving such a control at ultrafast timescales, however, is an outstanding challenge, as it requires a deep understanding of the dynamics of the collectively coupled molecular excitation and the nanoconfined electromagnetic fields. Here, we investigate the dynamics of collective polariton states, realized by coupling molecular photoswitches to optically anisotropic plasmonic nanoantennas. Pump-probe experiments reveal an ultrafast collapse of polaritons to a single-molecule transition triggered by femtosecond-pulse excitation at room-temperature. Through a synergistic combination of experiments and quantum mechanical modelling, we show that the response of the system is governed by intramolecular dynamics, occurring one order of magnitude faster with respect to the unperturbed excited molecule relaxation to the ground state.
Econometric analysis of selected health issues in Australia
Creators: name: Zhang., Xiaohui
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Lorentz Hypersurfaces satisfying $\triangle \vec {H}= α\vec {H}$ with non diagonal shape operator
Creators: name: Deepika
name: Arvanitoyeorgos, Andreas
name: Gupta, Ram Shankar
Publisher: name: arXiv
Year: 2016
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53D12, 53C40, 53C42

description: We study Lorentz hypersurfaces $M_{1}^{n}$ in $E_{1}^{n+1}$ satisfying $\triangle \vec {H}= α\vec {H}$ with non diagonal shape operator, having complex eigenvalues. We prove that every such Lorentz hypersurface in $E_{1}^{n+1}$ having at most five distinct principal curvatures has constant mean curvature.
description: 13 pages. arXiv admin note: text overlap with arXiv:1610.03005
Moving Goods in Kapiri Mposhi, Zambia:
Creators: name: Monson, Jamie
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: In den 970er Jahren wurde die TAZARA mit chinesischer Unterstützung gebaut, um den sambischen Kupfergürtel mit dem Indischen Ozean zu verbinden. Die Linie verbindet Dar es Salaam mit Kapiri Mposhi, zu dieser Zeit eine wenig bekannte Endstation der Eisenbahnlinie. Für Sambier jedoch ist Kapiri Mposhi kein Endpunkt, sondern ein Zentrum. Dieser Artikel untersucht die Geschichte von Kapiri Mposhi als Eisenbahnstadt aus der Perspektive des Lastentransports. Im TAZARA-Trockenhafen ist der Umschlag abhängig von Teams von Lastenträgern. Für die Träger im Eisenbahnbetrieb von Kapiri Mposhi wurde der Lebensunterhalt allerdings im Laufe der Zeit unzuverlässig. Als Reaktion auf die Unsicherheit gründeten die Träger Vereine, die versuchen, sowohl die soziale Sicherheit ihrer Mitglieder zu gewährleisten als auch die Auswirkungen der schwankenden Warenströme und des ungleichmäßigen Eisenbahnbetriebs auf ihre Arbeit zu lindern. Somit ermöglichen sie das Funktionieren dieses für Mittelafrika entscheidenden Zugangs zu transnationalen Handelsnetzwerken.
description: Comparativ, Vol 25 No 4 (2015): From Railway Juncture to Portal of Globalization: Making Globalization Work in African and South Asian Railway Towns
Single machine scheduling with job-dependent machine deterioration
Creators: name: Luo, Wenchang
name: Xu, Yao
name: Tong, Weitian
name: Lin, Guohui
Publisher: name: arXiv
Year: 2016
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: FOS: Computer and information sciences

description: We consider the single machine scheduling problem with job-dependent machine deterioration. In the problem, we are given a single machine with an initial non-negative maintenance level, and a set of jobs each with a non-preemptive processing time and a machine deterioration. Such a machine deterioration quantifies the decrement in the machine maintenance level after processing the job. To avoid machine breakdown, one should guarantee a non-negative maintenance level at any time point; and whenever necessary, a maintenance activity must be allocated for restoring the machine maintenance level. The goal of the problem is to schedule the jobs and the maintenance activities such that the total completion time of jobs is minimized. There are two variants of maintenance activities: in the partial maintenance case each activity can be allocated to increase the machine maintenance level to any level not exceeding the maximum; in the full maintenance case every activity must be allocated to increase the machine maintenance level to the maximum. In a recent work, the problem in the full maintenance case has been proven NP-hard; several special cases of the problem in the partial maintenance case were shown solvable in polynomial time, but the complexity of the general problem is left open. In this paper we first prove that the problem in the partial maintenance case is NP-hard, thus settling the open problem; we then design a $2$-approximation algorithm.
description: 15 pages
Using Capsule Networks to Classify Digitally Modulated Signals with Raw I/Q Data
Creators: name: Latshaw, James A.
name: Popescu, Dimitrie C.
name: Snoap, John A.
name: Spooner, Chad M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Machine learning has become a powerful tool for solving problems in various engineering and science areas, including the area of communication systems. This paper presents the use of capsule networks for classification of digitally modulated signals using the I/Q signal components. The generalization ability of a trained capsule network to correctly classify the classes of digitally modulated signals that it has been trained to recognize is also studied by using two different datasets that contain similar classes of digitally modulated signals but that have been generated independently. Results indicate that the capsule networks are able to achieve high classification accuracy. However, these networks are susceptible to the datashift problem which will be discussed in this paper.
description: 6 pages, 9 figures, to be published in IEEE ICC 2022: IEEE International Conference on Communications 2022
The Belgian Base at Kigoma’s Railhead (1920s–1930s).
Creators: name: Castryck, Geert
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Das Stadtgebiet um Kigoma dient seit der Mitte des 9. Jahrhunderts als Drehscheibe zwischen der Region um den Tanganjikasee und dem Indischen Ozean. Obwohl es seither insgesamt an globaler Bedeutung verloren hat, bewirkten die von den Deutschen gebaute Eisenbahn zwischen Dar es Salaam und Kigoma und der belgische Konzessionshafen am Kopfbahnhof Kigomas in den Jahren bis 930 einen kurzzeitigen Aufschwung. Kigoma als mit dem Indischen Ozean verbundener Inlandshafen stellte die kürzeste Verbindung zwischen der mineralreichen Region Katanga und dem Weltmarkt dar. Im Rahmen eines belgisch-britischen Abkommens nach dem Ersten Weltkrieg wurde diese Verbindung unter belgische Führung gestellt. Dieser Artikel argumentiert, dass der kurzlebige Erfolg von Kigoma um 930 durch Pragmatismus ermöglicht wurde. Statt auf formalen Rechten zu beharren, haben alle Beteiligten vor Ort einen reibungslosen Betrieb des Hafens bevorzugt. Sobald das Ausmaß der belgischen extraterritorialen Rechte und die Eingrenzungen der britischen Souveränität aber klar wurden, verlor der Hafen wieder an globaler Bedeutung.
description: Comparativ, Vol 25 No 4 (2015): From Railway Juncture to Portal of Globalization: Making Globalization Work in African and South Asian Railway Towns
Amplification of matter rogue waves and breathers in quasi-two-dimensional Bose-Einstein condensates
Creators: name: Manikandan, K.
name: Senthilvelan, M.
name: Kraenkel, R. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We construct rogue wave and breather solutions of a quasi-two-dimensional Gross-Pitaevskii equation with a time-dependent interatomic interaction and external trap. We show that the trapping potential and an arbitrary functional parameter that present in the similarity transformation should satisfy a constraint for the considered equation to be integrable and yield the desired solutions. We consider two different forms of functional parameters and investigate how the density of the rogue wave and breather profiles vary with respect to these functional parameters. We also construct vector localized solutions of a two coupled quasi-two-dimensional Bose-Einstein condensate system. We then investigate how the vector localized density profiles modify in the constant density background with respect to the functional parameters. Our results may help to manipulate matter rogue waves experimentally in the two-dimensional Bose-Einstein condensate systems.
description: 16 pages, Published in Eur. Phys. J. B
TC-Driver: Trajectory Conditioned Driving for Robust Autonomous Racing -- A Reinforcement Learning Approach
Creators: name: Ghignone, Edoardo
name: Baumann, Nicolas
name: Boss, Mike
name: Magno, Michele
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Autonomous racing is becoming popular for academic and industry researchers as a test for general autonomous driving by pushing perception, planning, and control algorithms to their limits. While traditional control methods such as MPC are capable of generating an optimal control sequence at the edge of the vehicles physical controllability, these methods are sensitive to the accuracy of the modeling parameters. This paper presents TC-Driver, a RL approach for robust control in autonomous racing. In particular, the TC-Driver agent is conditioned by a trajectory generated by any arbitrary traditional high-level planner. The proposed TC-Driver addresses the tire parameter modeling inaccuracies by exploiting the heuristic nature of RL while leveraging the reliability of traditional planning methods in a hierarchical control structure. We train the agent under varying tire conditions, allowing it to generalize to different model parameters, aiming to increase the racing capabilities of the system in practice. The proposed RL method outperforms a non-learning-based MPC with a 2.7 lower crash ratio in a model mismatch setting, underlining robustness to parameter discrepancies. In addition, the average RL inference duration is 0.25 ms compared to the average MPC solving time of 11.5 ms, yielding a nearly 40-fold speedup, allowing for complex control deployment in computationally constrained devices. Lastly, we show that the frequently utilized end-to-end RL architecture, as a control policy directly learned from sensory input, is not well suited to model mismatch robustness nor track generalization. Our realistic simulations show that TC-Driver achieves a 6.7 and 3-fold lower crash ratio under model mismatch and track generalization settings, while simultaneously achieving lower lap times than an end-to-end approach, demonstrating the viability of TC-driver to robust autonomous racing.
description: 6 pages, 4 figures, 3 tables, ICRA, OPPORTUNITIES AND CHALLENGES WITH AUTONOMOUS RACING, IEEE
A City Constructed by ‘des gens d’ailleurs’.
Creators: name: Boonen, Sofie
name: Lagae, Johan
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Die Gründung der Stadt Lubumbashi (damals Elisabethville) kann als geopolitischer Akt der belgischen Regierung verstanden werden, um ihren Anspruch auf ein mineralreiches Gebiet zu sichern und den britischen Einfluss aus dem Süden zurückzudrängen. Doch die erste und bis zum Ende der 920er Jahre einzige Eisenbahn, die Lubumbashi mit der Außenwelt verbunden hat, blieb weiterhin ein wichtiger Vektor für den Zustrom von Waren, Menschen, Ideen und Praktiken aus dem Süden. Dieser Artikel kartiert die Siedlungsmuster der ‚second rate whites‘ (Griechen, Juden …) im europäischen Stadtzentrum auf Grundlage der Grundbucharchive und zeigt so, wie die ‚gens d‘ailleurs‘ (Menschen von anderswo) auf Rassenkonzepten beruhende Trennungen von Bevölkerungsgruppen in Lubumbashi verwischt haben. Obwohl die Kolonialbehörden räumliche Strategien entwickelt hatten, um den Zustrom von Zuwanderern zu kontrollieren, um ihre Siedlungsgewohnheiten zu kanalisieren und die Interaktion zwischen segregierten Gruppen einzudämmen, trugen diese Mittelgruppen dazu bei, Lubumbashi als ‚weltoffene‘ Stadt auszuprägen.
description: Comparativ, Vol 25 No 4 (2015): From Railway Juncture to Portal of Globalization: Making Globalization Work in African and South Asian Railway Towns
Quasi-localized charge approximation approach for the nonlinear structures in strongly coupled Yukawa systems
Creators: name: Kumar, Prince
name: Sharma, Devendra
Publisher: name: arXiv
Year: 2023
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Strongly coupled systems occupying the transitional range between the Wigner crystal and fluid phases are most dynamic constituents of the nature. Highly localized but strongly interacting elements in this phase posses enough thermal energy to trigger the transition between a variety of short to long range order phases. Nonlinear excitations are often the carriers of proliferating structural modifications in the strongly coupled Yukawa systems. Well represented by a laboratory dusty plasma, these systems show explicit propagation of nonlinear shocks and solitary structures both in experiments and in first principle simulations. The shorter scale length contributions remain absent at strong screening in present approximate models which nevertheless prescribe nonlinear solitary solutions that consequently lose their coherence in a numerical evolution of the system under a special implementation of the quasi-localized charge approximation formulation. The stable coherent structures self-consistently emerge following an initial transient in the numerical evolution which adapts QLCA approach to spatiotemporal domain for accessing the nonlinear excitations in the strong screening limit. The present kappa ~ 1 limit of the existing Yukawa fluid models to show agreement with the experiment and MD simulations has therefore been overcome and the coherent nonlinear excitaitons have become characterizable up to kappa ~ 2.7, before they becoming computationally challenging in present implementation.
description: 17 figures
A Convergent Adaptive Finite Element Method for Electrical Impedance Tomography
Creators: name: Jin, Bangti
name: Xu, Yifeng
name: Zou, Jun
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: In this work we develop and analyze an adaptive finite element method for efficiently solving electrical impedance tomography -- a severely ill-posed nonlinear inverse problem for recovering the conductivity from boundary voltage measurements. The reconstruction technique is based on Tikhonov regularization with a Sobolev smoothness penalty and discretizing the forward model using continuous piecewise linear finite elements. We derive an adaptive finite element algorithm with an a posteriori error estimator involving the concerned state and adjoint variables and the recovered conductivity. The convergence of the algorithm is established, in the sense that the sequence of discrete solutions contains a convergent subsequence to a solution of the optimality system for the continuous formulation. Numerical results are presented to verify the convergence and efficiency of the algorithm.
description: 27 pages, 9 figures
Durban as a Portal of Globalization:
Creators: name: Hyslop, Jonathan
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Zwischen den 880er und frühen 920er Jahren hat Durban sich vom unbedeutenden Hafen der britischen Kolonie Natal zum Haupthafen des neuen südafrikanischen Staates gewandelt. Dieser Artikel untersucht die Schlüsselrolle, die Otto Siedle, der in Deutschland geborene, aber in London aufgewachsene Agent des Schifffahrtsunternehmens Natal Direct Line, in diesem Prozess gespielt hat. Durch die Entwicklung von Hafenanlagen, Kohlebergwerken und Eisenbahnen hat der Konzern bei der Umwandlung von Durban in die maritime Verbindung zwischen den wirtschaftlich wichtigen Goldminen in Witwatersrand und der Weltwirtschaft eine führende Rolle gespielt. Der Beitrag untersucht diese Veränderungen mithilfe des Konzeptes der ‚Portale der Globalisierung‘. Er findet den Begriff für die Analyse der Einbindung von Natal in globale Netzwerke hilfreich, plädiert aber gleichzeitig dafür, Portale hierarchisch zu verstehen und die Bedeutung von Imperien im Gegensatz zu Nationalstaaten im Auge zu behalten. Die Fallstudie stützt die Ansicht, dass die Rolle lokaler Siedlerkapitalisten für die Gestaltung globaler Verbindungen innerhalb des britischen Empire erheblich war und dass es deshalb ein Fehler wäre, sich bei der Analyse des Aufbaus der imperialen Wirtschaft übermäßig auf the City of London zu konzentrieren.
description: Comparativ, Vol 25 No 4 (2015): From Railway Juncture to Portal of Globalization: Making Globalization Work in African and South Asian Railway Towns
Distinct Speed and Direction Memories of Migrating Dendritic Cells Diversify Their Search Strategies
Creators: name: Shaebani, M. Reza
name: Piel, Matthieu
name: Lautenschläger, Franziska
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Migrating cells exhibit various motility patterns, resulting from different migration mechanisms, cell properties, or cell-environment interactions. The complexity of cell dynamics is reflected, e.g., in the diversity of the observed forms of velocity autocorrelation function -- that has been widely served as a measure of diffusivity and spreading -- . By analyzing the dynamics of migrating dendritic cells in vitro, we disentangle the contributions of direction and speed to the velocity autocorrelation. We find that the ability of cells to maintain their speed or direction of motion is unequal, reflected in power-law decays of speed and direction autocorrelation functions with different exponents. The larger power-law exponent of the speed autocorrelation function indicates that the cells lose their speed memory considerably faster than the direction memory. Using numerical simulations, we investigate the influence of speed and direction memories as well as the direction-speed cross-correlation on the search time of a persistent random walker to find a randomly located target in confinement. Although the direction memory and direction-speed coupling play the major roles, we find that the speed autocorrelation can be also tuned to minimize the search time. Adopting an optimal speed memory can reduce the search time even up to 10% compared to uncorrelated spontaneous speeds. Our results suggest that migrating cells can improve their search efficiency, especially in crowded environments, through the directional or speed persistence or the speed-direction correlation.
description: 10 pages, 9 figures
Railway Imperialism.
Creators: name: Sinha, Nitin
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Jamalpur ist eine der ältesten Eisenbahnstädte in Indien. Dieser Artikel befasst sich anhand von Gründungsgeschichten der Stadt mit den ersten vier Jahrzehnten ihres Bestehens (860er– 900er Jahre), um so das Zusammenspiel der stadtspezifischen, regionalen und imperialen Faktoren, die das Entstehen der Stadt geprägt haben, zu verstehen. Er konzentriert sich insbesondere auf die Spannungen zwischen einer imperialen Politik der Abschottung und der moralischen Überlegenheit einer ‚weißen Arbeiterklasse‘ einerseits und der Angewiesenheit auf andere Bevölkerungsgruppen in der Stadt, der Region und dem Empire andererseits. Es wird argumentiert, dass es notwendig ist, über einen Lokal-Global-Gegensatz hinwegzukommen, um sowohl Einzelheiten als auch Zusammenhänge verstehen zu können. Der Artikel fordert dazu auf, Prozesse und Mechanismen zu lokalisieren und zu analysieren, die nicht nur Verbindungen und scheinbare Einheitlichkeit, sondern auch Abgrenzungen und Brüche erklären. Das Zusammenführen von scheinbaren Gegensätzen ermöglicht es, die Stadtgeschichte unter Berücksichtigung der Vielschichtigkeit von räumlichen Bezügen neu zu schreiben.
description: Comparativ, Vol 25 No 4 (2015): From Railway Juncture to Portal of Globalization: Making Globalization Work in African and South Asian Railway Towns
Black hole shadow and chaos bound violation in $f(T)$ teleparallel gravity
Creators: name: Addazi, Andrea
name: Capozziello, Salvatore
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We show that the so-called chaos bound, proposed by Maldacena, Shenker, and Stanford, can be violated in $f(T)$ teleparallel gravity. In particular, it is possible to select a new gravitational Lyapunov parameter, controlling chaotization of circular trajectories, in black hole photo-sphere, that can exceed the Maldacena, Shenker and Stanford thermal bound. This feature alters the standard quasi-normal modes and ringdown phase after black hole merging with intriguing implications for future gravitational wave detections and black hole shadow measurements. It is a general characteristic for several gravitational theories beyond standard General Relativity.
description: 5 pages, 1 figure, accepted for publication in Physics Letters B
Quantized anomalous Hall resistivity achieved in molecular beam epitaxy-grown MnBi2Te4 thin films
Creators: name: Bai, Yunhe
name: Li, Yuanzhao
name: Luan, Jianli
name: Liu, Ruixuan
name: Song, Wenyu
name: Chen, Yang
name: Ji, Peng-Fei
name: Zhang, Qinghua
name: Meng, Fanqi
name: Tong, Bingbing
name: Li, Lin
name: Jiang, Yuying
name: Gao, Zongwei
name: Gu, Lin
name: Zhang, Jinsong
name: Wang, Yayu
name: Xue, Qi-Kun
name: He, Ke
name: Feng, Yang
name: Feng, Xiao
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The intrinsic magnetic topological insulator MnBi2Te4 provides a feasible pathway to high temperature quantum anomalous Hall (QAH) effect as well as various novel topological quantum phases. Although quantized transport properties have been observed in exfoliated MnBi2Te4 thin flakes, it remains a big challenge to achieve molecular beam epitaxy (MBE)-grown MnBi2Te4 thin films even close to the quantized regime. In this work, we report the realization of quantized anomalous Hall resistivity in MBE-grown MnBi2Te4 thin films with the chemical potential tuned by both controlled in-situ oxygen exposure and top gating. We find that elongated post-annealing obviously elevates the temperature to achieve quantization of the Hall resistivity, but also increases the residual longitudinal resistivity, indicating a picture of high-quality QAH puddles weakly coupled by tunnel barriers. These results help to clarify the puzzles in previous experimental studies on MnBi2Te4 and to find a way out of the big difficulty in obtaining MnBi2Te4 samples showing quantized transport properties.
description: 4 figures
Data mining in the automobile insurance industry
Creators: name: Yeo., Ai Cheo
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Zwischen Zentren und Peripherien.
Creators: name: Hertel, Patricia
name: Baumeister, Martin
name: Sala, Roberto
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Since the so-called “spatial turn”, historians have been intensively dealing with concepts of space and macro-regions. While Eastern Europe has received considerable attention, fewer studies have examined Western Europe and its heterogeneities during the Cold War era, especially beyond the examples of Great Britain, France, or Germany. The current issue analyses the internal differences in Western Europe from the 1940s until the end of the 1970s. It explores in particular the contrast between the geopolitical discourse of a homogeneous “Western bloc” and competing concepts that stressed the internal differences between the countries and regions considered to belong to the geopolitical “West”, such as the idea of industrialized “Northern” and agrarian “Southern” countries and regions. By focusing on the role of experts in national and transnational spheres, their discourses, as well as approaches to economic, political, and cultural differences, it demonstrates, via implicit and explicit concepts of a “North” and a “South”, how the idea of the “West” was negotiated and discussed.
description: Comparativ, Vol 25 No 3 (2015): Die Verhandlung des Westens. Wissenseliten und die Heterogenität Westeuropas nach 1945
The properties of heavy elements in giant planet envelopes
Creators: name: Soubiran, Francois
name: Militzer, Burkhard
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The core accretion model for giant planet formation suggests a two layer picture for the initial structure of Jovian planets, with heavy elements in a dense core and a thick H-He envelope. Late planetesimal accretion and core erosion could potentially enrich the H-He envelope in heavy elements, which is supported by the three-fold solar metallicity that was measured in Jupiter's atmosphere by the Galileo entry probe. In order to reproduce the observed gravitational moments of Jupiter and Saturn, models for their interiors include heavy elements, $Z$, in various proportions. However, their effect on the equation of state of the hydrogen-helium mixtures has not been investigated beyond the ideal mixing approximation. In this article, we report results from \textit{ab initio} simulations of fully interacting H-He-$Z$ mixtures in order to characterize their equation of state and to analyze possible consequences for the interior structure and evolution of giant planets. Considering C, N, O, Si, Fe, MgO and SiO$_2$, we show that the behavior of heavy elements in H-He mixtures may still be represented by an ideal mixture if the effective volumes and internal energies are chosen appropriately. In the case of oxygen, we also compute the effect on the entropy. We find the resulting changes in the temperature-pressure profile to be small. A homogeneous distribution of 2\% oxygen by mass changes the temperature in Jupiter's interior by only 80 K.
description: 14 pages, 14 figures. Accepted for publication in the Astrophysical Journal
Weak Gravity Conjecture as a Razor Criterium for Exotic D-brane instantons
Creators: name: Addazi, Andrea
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss implications of Weak gravity conjecture (WGC) for exotic D-brane instantons. In particular, WGC leads to indirect stringent bounds on non-perturbative superpotentials generated by exotic instantons, with many implications for phenomenology: R-parity violating processes, neutrino mass, $μ$-problem, Neutron-Antineutron transitions and collider physics.
description: Few formal typos corrected
Search for light long-lived neutral particles that decay to collimated pairs of leptons or light hadrons in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
Creators: name: ATLAS Collaboration
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: A search for light long-lived neutral particles with masses in the $O$(MeV-GeV) range is presented. The analysis targets the production of long-lived dark photons in the decay of a Higgs boson produced via gluon-gluon fusion or in association with a $W$ boson. Events that contain displaced collimated Standard Model fermions reconstructed in the calorimeter or muon spectrometer are selected in 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV $pp$ collision data collected by the ATLAS detector at the LHC. Background estimates for contributions from Standard Model processes and instrumental effects are extracted from data. The observed event yields are consistent with the expected background. Exclusion limits are reported on the production cross-section times branching fraction as a function of the mean proper decay length $cτ$ of the dark photon, or as a function of the dark-photon mass and kinetic mixing parameter that quantifies the coupling between the Standard Model and potential hidden (dark) sectors. A Higgs boson branching fraction above 1% is excluded at 95% CL for a Higgs boson decaying into two dark photons for dark-photon mean proper decay lengths between 10 mm and 250 mm and dark photons with masses between 0.4 GeV and 2 GeV.
description: 52 pages in total, 13 figures, 5 tables. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2019-05