cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Constraints on neutron star superfluidity from the cooling neutron star in Cassiopeia A using all Chandra ACIS-S observations
Creators: name: Shternin, Peter S.
name: Ofengeim, Dmitry D.
name: Heinke, Craig O.
name: Ho, Wynn C. G.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Analysis of Chandra observations of the neutron star (NS) in the centre of the Cassiopeia A supernova remnant taken in the subarray (FAINT) mode of the ACIS detector performed by Posselt and collaborators revealed, after inclusion of the most recent (May 2020) observations, a significant decrease of the source surface temperature from 2006 to 2020. The obtained cooling rate is consistent with those obtained from analysis of the 2000$-$2019 data taken in the GRADED mode of the ACIS detector, which is potentially more strongly affected by instrumental effects. We performed a joint spectral analysis using all ACIS data to constrain the NS parameters and cooling rate. We constrain the mass of the Cassiopeia A NS at $M=1.55\pm0.25~M_\odot$, and its radius at $R=13.5\pm 1.5$ km. The surface temperature cooling rate is found to be $2.2\pm 0.3$ per cent in 10 years if the absorbing hydrogen column density is allowed to vary and $1.6\pm 0.2$ per cent in 10 years if it is fixed. The observed cooling can be explained by enhanced neutrino emission from the superfluid NS interior due to Cooper Pair Formation (CPF) process. Based on analysis of all ACIS data, we constrain the maximal critical temperature of triplet neutron pairing within the NS core at $(4-9.5)\times 10^{8}$ K. In accordance with previous studies, the required effective strength of the CPF neutrino emission is at least a factor of 2 higher than existing microscopic calculations suggest.
description: 20 pages, 17 figures. Accepted for publication in MNRAS
Full-depth englacial vertical ice sheet velocities measured using phase-sensitive radar
Creators: name: Kingslake, Jonathan
name: Hindmarsh, Richard C. A.
name: Aoalgeirsdottir, Guofinna
name: Conway, Howard
name: Corr, Hugh F. J.
name: Gillet-Chaulet, Fabien
name: Martin, Carlos
name: King, Edward C.
name: Mulvaney, Robert
name: Pritchard, Hamish D.
Publisher: name: Columbia University
Year: 2014
Subjects: subject: Ice--Dynamics
subject: Glaciology--Methodology
subject: Ice sheets
subject: Geophysics
subject: FOS: Earth and related environmental sciences
subject: Hydrology

description: We describe a geophysical technique to measure englacial vertical velocities through to the beds of ice sheets without the need for borehole drilling. Using a ground-based phase-sensitive radio echo sounder (pRES) during seven Antarctic field seasons, we measure the temporal changes in the position of englacial reflectors within ice divides up to 900 m thick on Berkner Island, Roosevelt Island, Fletcher Promontory, and Adelaide Island. Recorded changes in reflector positions yield “full-depth” profiles of vertical ice velocity that we use to examine spatial variations in ice flow near the divides. We interpret these variations by comparing them to the results of a full-Stokes simulation of ice divide flow, qualitatively validating the model and demonstrating that we are directly detecting an ice-dynamical phenomenon called the Raymond Effect. Using pRES, englacial vertical ice velocities can be measured in higher spatial resolution than is possible using instruments installed within the ice. We discuss how these measurements could be used with inverse methods to measure ice rheology and to improve ice core dating by incorporating pRES-measured vertical velocities into age modeling.
Rotating black holes in 4d gauged supergravity
Creators: name: Gnecchi, Alessandra
name: Hristov, Kiril
name: Klemm, Dietmar
name: Toldo, Chiara
name: Vaughan, Owen
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present new results towards the construction of the most general black hole solutions in four-dimensional Fayet-Iliopoulos gauged supergravities. In these theories black holes can be asymptotically AdS and have arbitrary mass, angular momentum, electric and magnetic charges and NUT charge. Furthermore, a wide range of horizon topologies is allowed (compact and noncompact) and the complex scalar fields have a nontrivial radial and angular profile. We construct a large class of solutions in the simplest single scalar model with prepotential $F = -i X^0 X^1$ and discuss their thermodynamics. Moreover, various approaches and calculational tools for facing this problem with more general prepotentials are presented.
description: 37 pages, 1 figure
Secure Outage Analysis of RIS-Assisted Communications with Discrete Phase Control
Creators: name: Shi, Wei
name: Xu, Jindan
name: Xu, Wei
name: Di Renzo, Marco
name: Zhao, Chunming
Publisher: name: arXiv
Year: 2022
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This correspondence investigates a reconfigurable intelligent surface (RIS)-assisted wireless communication system with security threats. The RIS is deployed to enhance the secrecy outage probability (SOP) of the data sent to a legitimate user. By deriving the distributions of the received signal-to-noise-ratios (SNRs) at the legitimate user and the eavesdropper, we formulate, in a closed-form expression, a tight bound for the SOP under the constraint of discrete phase control at the RIS. The SOP is characterized as a function of the number of antenna elements, $N$, and the number of discrete phase choices, $2^b$. It is revealed that the performance loss in terms of SOP due to the discrete phase control is ignorable for large $N$ when $b\!\geq\!3$. In addition, we explicitly quantify this SOP loss when binary phase shifts with $b\!=\!1$ is utilized. It is identified that increasing the RIS antenna elements by $1.6$ times can achieve the same SOP with binary phase shifts as that by the RIS with ideally continuous phase shifts. Numerical simulations are conducted to verify the accuracy of these theoretical observations.
description: Accepted by IEEE Transactions on Vehicular Technology
A Data-Driven Search For Mid-Infrared Excesses Among Five Million Main-Sequence FGK Stars
Creators: name: Contardo, Gabriella
name: Hogg, David W.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Stellar infrared excesses can indicate various phenomena of interest, from protoplanetary disks to debris disks, or (more speculatively) techno-signatures along the lines of Dyson spheres. In this paper, we conduct a large search for such excesses, designed as a data-driven contextual anomaly detection pipeline. We focus our search on FGK stars close to the main sequence to favour non-young host stars. We look for excess in the mid-infrared, unlocking a large sample to search in while favouring extreme IR excess akin to the ones produced by Extreme Debris Disks (EDD). We combine observations from ESA Gaia DR3, 2MASS, and the unWISE of NASA WISE, and create a catalogue of 4,898,812 stars with $G < 16$ mag. We consider a star to have an excess if it is substantially brighter in $W1$ and $W2$ bands than what is predicted from an ensemble of machine-learning models trained on the data, taking optical and near-infrared information as input features. We apply a set of additional cuts (derived from the ML models and the objects' astronomical features) to avoid false-positive and identify a set of 53 objects (a rate of $1.1\times 10^{-5}$), including one previously identified EDD candidate. Typical infrared-excess fractional luminosities we find are in the range 0.005 to 0.1, consistent with known EDDs.
description: 23 pages, 17 figures, 2 tables. Candidates' IDs and (some) code available at https://github.com/contardog/NotATechnosignatureSearch . Accepted at AJ. Revised version uploaded with candidates table added in pdf, added search for nearby radio sources
Universality of critical magnetic field in holographic superconductor
Creators: name: Momeni, D.
name: Myrzakulov, R.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this letter we study aspects of the holographic superconductors analytically in the presence of a constant external magnetic field. We show that the critical temperature and critical magnetic field can be calculated at nonzero temperature. We detect the Meissner effect in such superconductors. A universal relation between black hole mass $ M$ and critical magnetic field $H_c$ is proposed as $\frac{H_c}{M^{2/3}}\leq 0.687365$. We discuss some aspects of phase transition in terms of black hole entropy and the Bekenstein's entropy to energy upper bound.
description: Accepted version as a Letter
Trends in Energy Estimates for Computing in AI/Machine Learning Accelerators, Supercomputers, and Compute-Intensive Applications
Creators: name: Shankar, Sadasivan
name: Reuther, Albert
Publisher: name: arXiv
Year: 2022
Subjects: subject: Hardware Architecture (cs.AR)
subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences
subject: C.4; I.2
subject: 68U01

description: We examine the computational energy requirements of different systems driven by the geometrical scaling law, and increasing use of Artificial Intelligence or Machine Learning (AI-ML) over the last decade. With more scientific and technology applications based on data-driven discovery, machine learning methods, especially deep neural networks, have become widely used. In order to enable such applications, both hardware accelerators and advanced AI-ML methods have led to the introduction of new architectures, system designs, algorithms, and software. Our analysis of energy trends indicates three important observations: 1) Energy efficiency due to geometrical scaling is slowing down; 2) The energy efficiency at the bit-level does not translate into efficiency at the instruction-level, or at the system-level for a variety of systems, especially for large-scale AI-ML accelerators or supercomputers; 3) At the application level, general-purpose AI-ML methods can be computationally energy intensive, off-setting the gains in energy from geometrical scaling and special purpose accelerators. Further, our analysis provides specific pointers for integrating energy efficiency with performance analysis for enabling high-performance and sustainable computing in the future.
description: 8 pages, 9 figures, Submitted to Proceedings of IEEE Conference on High Performance Extreme Computing (HPEC) 2022
Different pasts, contested presents and desired futures: local narratives and identities in the co-production of a shared wind energy ownership model
Creators: name: Elkjær, Lene Gjørtler
name: Rudolph, David Philipp
name: Horst, Maja
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Science Policy

description: Previously, local actors have often had a stake in renewable energy projects through cooperative ownership and other variants of community energy configurations. However, the increase in project size and necessary investments as well as policy shifts towards auctions and “local energy” have made it difficult for communities to obtain a stake in such developments, while also increasing the potential for controversies. This article investigates the construction of a shared ownership model of a utility-scale wind farm by identifying three narratives presented by local actors and exposes how these narratives position them to shape the ownership configuration of the project to their advantage. We show how local actors’ stories construct the development in the local area as business as usual, tragic degradation or potentially an epic turn-around. These different constructions of the wind power project draw on different historical developments, construct different presents and envision different futures as a result of the proposed wind power project. Furthermore, we disentangle how these constructions and different perceptions of time employed by the actor groups legitimize different ownership structures and project configurations, thus co-producing the project and the trajectory of local development. We end by arguing that such narratives related to the (il)legitimacy of renewable energy projects are important for the ability to move the renewable energy transition forward in a just manner.
Chaotic dynamics of a glaciohydraulic model
Creators: name: Kingslake, Jonathan
Publisher: name: Columbia University
Year: 2015
Subjects: subject: Hydrologic models
subject: Runoff
subject: Subglacial lakes
subject: Geophysics
subject: FOS: Earth and related environmental sciences
subject: Hydrology

description: A model subglacial drainage system, coupled to an ice-dammed reservoir that receives a time-varying meltwater input, is described and analysed. In numerical experiments an ice-marginal lake drains through a subglacial channel, producing periodic floods, and fills with meltwater at a rate dependent on air temperature, which varies seasonally with a peak value of T m. The analysis reveals regions of T m parameter space corresponding to 'mode locking', where flood repeat time is independent of T m; resonance, where decreasing T m counter-intuitively increases flood size; and chaotic dynamics, where flood cycles are sensitive to initial conditions, never repeat and exhibit phase-space mixing. Bifurcations associated with abrupt changes in flood size and timing within the year separate these regions. This is the first time these complex dynamics have been displayed by a glaciohydraulic model and these findings have implications for our understanding of ice-marginal lakes, moulins and subglacial lakes.
Investigation of a universal behavior between Néel temperature and staggered magnetization density for a three-dimensional quantum antiferromagnet
Creators: name: Kao, M. -T.
name: Jiang, F. -J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We simulate the three-dimensional quantum Heisenberg model with a spatially anisotropic ladder pattern using the first principles Monte Carlo method. Our motivation is to investigate quantitatively the newly established universal relation $T_N/\sqrt{c^3}$ $\propto$ ${\cal M}_s$ near the quantum critical point (QCP) associated with dimerization. Here $T_N$, $c$, and ${\cal M}_s$ are the Néel temperature, the spinwave velocity, and the staggered magnetization density, respectively. For all the physical quantities considered here, such as $T_N$ and ${\cal M}_s$, our Monte Carlo results agree nicely with the corresponding results determined by the series expansion method. In addition, we find it is likely that the effect of a logarithmic correction, which should be present in (3+1)-dimensions, to the relation $T_N/\sqrt{c^3}$ $\propto$ ${\cal M}_s$ near the investigated QCP only sets in significantly in the region with strong spatial anisotropy.
description: 5 pages, 7 figures, 2 tables
Summation of coefficients of polynomials on $\ell_{p}$ spaces
Creators: name: Dimant, Verónica
name: Sevilla-Peris, Pablo
Publisher: name: arXiv
Year: 2013
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics

description: We investigate the summability of the coefficients of $m$-homogeneous polynomials and $m$-linear mappings defined on $\ell_{p}$-spaces. In our research we obtain results on the summability of the coefficients of $m$-linear mappings defined on $\ell_{p_{1}} \times \cdots \times \ell_{p_{m}}$. The first results in this respect go back to Littlewood and Bohnenblust and Hille (for bilinear and $m$-linear forms on $c_{0}$) and Hardy and Littlewood and Praciano-Pereira (for bilinear and $m$-linear forms on arbitrary $\ell_{p}$-spaces). Our results recover and in some case complete these old results through a general approach on vector valued $m$-linear mappings.
Hydropower policy in Ecuador: an analysis from environmental perspective and recommendations for future policymaking
Creators: name: Briones-Hidrovo, Andrei
name: Uche, Javier
name: Martínez-Gracia, Amaya
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Science Policy
subject: Mental Health
subject: Plant Biology

description: Renewable energies are vital to tackle climate change and reduce environmental issues. In this sense, hydropower plays a key role. Broadly speaking, hydropower is perceived as a climate ally and considered environmentally sustainable. However, its development is still controversial due to the well-known environmental and ecological impacts that put its environmental sustainability in question. In this sense, this study aims to analyse and discuss hydropower development and policy in Ecuador from an environmental perspective. The analysis addresses the research question of to what extent the business-as-usual hydropower policy is compatible and consistent with national environmental sustainability and Buen Vivir (Good Living) goals. For such purpose, the analysis is conducted by applying a proposed conceptual framework composed of critical elements such as Buen Vivir principles, rights of nature and the evidence on the environmental sustainability of hydropower. The analysis highlights the main environmental drawbacks of the BAU-HP policy and finds that the current development and policy of hydropower is ultimately detrimental to achieving national environmental sustainability and Buen Vivir. Moreover, it easily infringes the Rights of Nature and conflicts with the conservation of ecosystems and biodiversity. Following the findings, several environmental sustainability-oriented recommendations are suggested for future hydropower policymaking.
Rayleigh–Taylor instabilities with anisotropic lithospheric viscosity
Creators: name: Lev, Einat
name: Hager, Bradford H.
Publisher: name: Columbia University
Year: 2008
Subjects: subject: Geodynamics--Methodology
subject: Lithosphere
subject: Rheology
subject: Anisotropy
subject: Geophysics
subject: FOS: Earth and related environmental sciences

description: Rocks often develop fabric when subject to deformation, and this fabric causes anisotropy of physical properties such as viscosity and seismic velocities. We employ 2-D analytical solutions and numerical flow models to investigate the effect of anisotropic viscosity (AV) on the development of Rayleigh–Taylor instabilities, a process strongly connected to lithospheric instabilities. Our results demonstrate a dramatic effect of AV on the development of instabilities—their timing, location, and, most notably, their wavelength are strongly affected by the initial fabric. Specifically, we find a significant increase in the wavelength of instability in the presence of AV which favours horizontal shear. We also find that an interplay between regions with different initial fabric gives rise to striking irregularities in the downwellings. Our study shows that for investigations of lithospheric instabilities, and likely of other mantle processes, the approximation of isotropic viscosity may not be adequate, and that AV should be included.
A stochastic model for quantum measurement
Creators: name: Budiyono, Agung
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We develop a statistical model of microscopic stochastic deviation from classical mechanics based on a stochastic processes with a transition probability that is assumed to be given by an exponential distribution of infinitesimal stationary action. We apply the statistical model to stochastically modify a classical mechanical model for the measurement of physical quantities reproducing the prediction of quantum mechanics. The system+apparatus always have a definite configuration all the time as in classical mechanics, fluctuating randomly following a continuous trajectory. On the other hand, the wave function and quantum mechanical Hermitian operator corresponding to the physical quantity arise formally as artificial mathematical constructs. During a single measurement, the wave function of the whole system+apparatus evolves according to a Schrödinger equation and the configuration of the apparatus acts as the pointer of the measurement so that there is no wave function collapse. We will also show that while the result of each single measurement event does not reveal the actual value of the physical quantity prior to measurement, its average in an ensemble of identical measurement is equal to the average of the actual value of the physical quantity prior to measurement over the distribution of the configuration of the system.
description: 12 pages, accepted for publication in Journal of Statistical Mechanics: Theory and Experiment. arXiv admin note: substantial text overlap with arXiv:1301.5345
BASS XXXIX: Swift-BAT AGN with changing-look optical spectra
Creators: name: Temple, Matthew J.
name: Ricci, Claudio
name: Koss, Michael J.
name: Trakhtenbrot, Benny
name: Bauer, Franz E.
name: Mushotzky, Richard
name: Rojas, Alejandra F.
name: Caglar, Turgay
name: Harrison, Fiona
name: Oh, Kyuseok
name: Gonzalez, Estefania Padilla
name: Powell, Meredith C.
name: Ricci, Federica
name: Riffel, Rogério
name: Stern, Daniel
name: Urry, C. Megan
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Changing-look (CL) AGN are unique probes of accretion onto supermassive black holes (SMBHs), especially when simultaneous observations in complementary wavebands allow investigations into the properties of their accretion flows. We present the results of a search for CL behaviour in 412 Swift-BAT detected AGN with multiple epochs of optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS). 125 of these AGN also have 14-195 keV ultra-hard X-ray light-curves from Swift-BAT which are contemporaneous with the epochs of optical spectroscopy. Eight CL events are presented for the first time, where the appearance or disappearance of broad Balmer line emission leads to a change in the observed Seyfert type classification. Combining with known events from the literature, 21 AGN from BASS are now known to display CL behaviour. Nine CL events have 14-195 keV data available, and five of these CL events can be associated with significant changes in their 14-195 keV flux from BAT. The ultra-hard X-ray flux is less affected by obscuration and so these changes in the 14-195 keV band suggest that the majority of our CL events are not due to changes in line-of-sight obscuration. We derive a CL rate of 0.7-6.2 per cent on 10-25 year time-scales, and show that many transitions happen within at most a few years. Our results motivate further multi-wavelength observations with higher cadence to better understand the variability physics of accretion onto SMBHs.
description: 14 pages, 7 figures, plus appendix. v2: updated references. Published in MNRAS
MyoPS-Net: Myocardial Pathology Segmentation with Flexible Combination of Multi-Sequence CMR Images
Creators: name: Qiu, Junyi
name: Li, Lei
name: Wang, Sihan
name: Zhang, Ke
name: Chen, Yinyin
name: Yang, Shan
name: Zhuang, Xiahai
Publisher: name: arXiv
Year: 2022
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Myocardial pathology segmentation (MyoPS) can be a prerequisite for the accurate diagnosis and treatment planning of myocardial infarction. However, achieving this segmentation is challenging, mainly due to the inadequate and indistinct information from an image. In this work, we develop an end-to-end deep neural network, referred to as MyoPS-Net, to flexibly combine five-sequence cardiac magnetic resonance (CMR) images for MyoPS. To extract precise and adequate information, we design an effective yet flexible architecture to extract and fuse cross-modal features. This architecture can tackle different numbers of CMR images and complex combinations of modalities, with output branches targeting specific pathologies. To impose anatomical knowledge on the segmentation results, we first propose a module to regularize myocardium consistency and localize the pathologies, and then introduce an inclusiveness loss to utilize relations between myocardial scars and edema. We evaluated the proposed MyoPS-Net on two datasets, i.e., a private one consisting of 50 paired multi-sequence CMR images and a public one from MICCAI2020 MyoPS Challenge. Experimental results showed that MyoPS-Net could achieve state-of-the-art performance in various scenarios. Note that in practical clinics, the subjects may not have full sequences, such as missing LGE CMR or mapping CMR scans. We therefore conducted extensive experiments to investigate the performance of the proposed method in dealing with such complex combinations of different CMR sequences. Results proved the superiority and generalizability of MyoPS-Net, and more importantly, indicated a practical clinical application.
Cosmic Neutrino Decoupling and its Observable Imprints: Insights from Entropic-Dual Transport
Creators: name: Bond, J. Richard
name: Fuller, George M.
name: Grohs, Evan
name: Meyers, Joel
name: Wilson, Matthew James
Publisher: name: arXiv
Year: 2024
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Very different processes characterize the decoupling of neutrinos to form the cosmic neutrino background (C$ν$B) and the much later decoupling of photons from thermal equilibrium to form the cosmic microwave background (CMB). The C$ν$B emerges from the fuzzy, energy-dependent neutrinosphere and encodes the physics operating in the early universe in the temperature range $T\sim 10\,{\rm MeV}$ to $T\sim10\,{\rm keV}$. This is the epoch where beyond Standard Model (BSM) physics may be influential in setting the light element abundances and the necessarily distorted fossil neutrino energy spectra. Here we use techniques honed in extensive CMB studies to analyze the C$ν$B as calculated in detailed neutrino energy transport and nuclear reaction simulations. Our moment method, relative entropy, and differential visibility approach can leverage future high precision CMB and primordial abundance measurements to provide new insights into the C$ν$B and any BSM physics it encodes. We demonstrate that the evolution of the energy spectrum of the C$ν$B throughout the weak decoupling epoch is accurately captured in the Standard Model by only three parameters per species, a non-trivial conclusion given the deviation from thermal equilibrium. Furthermore, we can interpret each of the three parameters as physical characteristics of a non-equilibrium system. The success of our compact description within the Standard Model motivates its use also in BSM scenarios. We demonstrate how observations of primordial light element abundances can be used to place constraints on the C$ν$B energy spectrum, deriving response functions that can be applied for general C$ν$B spectral distortions. Combined with the description of those deviations that we develop here, our methods provide a convenient and powerful framework to constrain the impact of BSM physics on the C$ν$B.
description: v2: Added Figure 9, Appendix B, and references; Updated to match published version; v1: 50 pages, 14 figures
Fine-grained Population Mapping from Coarse Census Counts and Open Geodata
Creators: name: Metzger, Nando
name: Vargas-Muñoz, John E.
name: Daudt, Rodrigo C.
name: Kellenberger, Benjamin
name: Whelan, Thao Ton-That
name: Ofli, Ferda
name: Imran, Muhammad
name: Schindler, Konrad
name: Tuia, Devis
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Fine-grained population maps are needed in several domains, like urban planning, environmental monitoring, public health, and humanitarian operations. Unfortunately, in many countries only aggregate census counts over large spatial units are collected, moreover, these are not always up-to-date. We present POMELO, a deep learning model that employs coarse census counts and open geodata to estimate fine-grained population maps with 100m ground sampling distance. Moreover, the model can also estimate population numbers when no census counts at all are available, by generalizing across countries. In a series of experiments for several countries in sub-Saharan Africa, the maps produced with POMELOare in good agreement with the most detailed available reference counts: disaggregation of coarse census counts reaches R2 values of 85-89%; unconstrained prediction in the absence of any counts reaches 48-69%.
Towards completing extrasolar systems with the TROY project
Creators: name: Balsalobre-Ruza, Olga
name: Lillo-Box, Jorge
Publisher: name: Zenodo
Year: 2023
Subjects: Exoplanets
Co-orbitals
Exotrojans

description: In this poster I will provide an overview of the status of our TROY project aiming at detecting and constraining the presence of co-orbital planets/bodies in extrasolar systems. Co-orbitals do exist in our Solar System in the form of small (max- 400 km in size) asteroids trapped in the Lagrangian points of six out of the eight planets. However, planet formation theories allow their formation up to planetary sizes and dynamical stability confirms these 1:1 resonances are indeed stable in the long-term. Exploring these configurations has remained in the to-do list of the exoplanet exploration. With the TROY project we aim at filling this gap from an observational point of view with strong implications in planet formation and evolution. The first conclusions of the project will be presented.
Multi-wavelength Diagnostics of the Precursor and Main phases of an M1.8 Flare on 2011 April 22
Creators: name: Awasthi, A. K.
name: Jain, R.
name: Gadhiya, P. D.
name: Aschwanden, M. J.
name: Uddin, W.
name: Srivastava, A. K.
name: Chandra, R.
name: Gopalswamy, N.
name: Nitta, N.
name: Yashiro, S.
name: Manoharan, P. K.
name: Choudhary, D. P.
name: Joshi, N. C.
name: Dwivedi, V. C.
name: Mahalakshmi, K.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We study the temporal, spatial and spectral evolution of the M1.8 flare, which occurred in NOAA AR 11195 (S17E31) on 22 April 2011, and explore the underlying physical processes during the precursors and their relation to the main phase. The study of the source morphology using the composite images in 131 °A wavelength observed by the SDO/AIA and 6-14 keV revealed a multiloop system that destabilized systematically during the precursor and main phases. In contrast, HXR emission (20-50 keV) was absent during the precursor phase, appearing only from the onset of the impulsive phase in the form of foot-points of emitting loop/s. This study has also revealed the heated loop-top prior to the loop emission, although no accompanying foot-point sources were observed during the precursor phase. We estimate the flare plasma parameters viz. T, EM, power-law index, and photon turn-over energy by forward fitting RHESSI spectral observations. The energy released in the precursor phase was thermal and constituted ~1 per cent of the total energy released during the flare. The study of morphological evolution of the filament in conjunction with synthesized T and EM maps has been carried out which reveals (a) Partial filament eruption prior to the onset of the precursor emission, (b) Heated dense plasma over the polarity inversion line and in the vicinity of the slowly rising filament during the precursor phase. Based on the implications from multi-wavelength observations, we propose a scheme to unify the energy release during the precursor and main phase emissions in which, the precursor phase emission has been originated via conduction front formed due to the partial filament eruption. Next, the heated leftover S-shaped filament has undergone slow rise and heating due to magnetic reconnection and finally erupted to produce emission during the impulsive and gradual phases.
description: 16 Pages, 11 Figures, Accepted for Publication in MNRAS Main Journal
North American Pancontinental Droughts in Model Simulations of the Last Millennium
Creators: name: Coats, Sloan John
name: Cook, Benjamin I.
name: Smerdon, Jason E.
name: Seager, Richard
Publisher: name: Columbia University
Year: 2015
Subjects: Paleoclimatology--Mathematical models
Climatic changes--Risk management
Meteorology
Droughts
Atmosphere

description: Pancontinental droughts in North America, or droughts that simultaneously affect a large percentage of the geographically and climatically distinct regions of the continent, present significant on-the-ground management challenges and, as such, are an important target for scientific research. The methodology of paleoclimate-model data comparisons is used herein to provide a more comprehensive understanding of pancontinental drought dynamics. Models are found to simulate pancontinental drought with the frequency and spatial patterns exhibited by the paleoclimate record. They do not, however, agree on the modes of atmosphere–ocean variability that produce pancontinental droughts because simulated El Niño–Southern Oscillation (ENSO), Pacific decadal oscillation (PDO), and Atlantic multidecadal oscillation (AMO) dynamics, and their teleconnections to North America, are different between models and observations. Despite these dynamical differences, models are able to reproduce large-magnitude centennial-scale variability in the frequency of pancontinental drought occurrence—an important feature of the paleoclimate record. These changes do not appear to be tied to exogenous forcing, suggesting that simulated internal hydroclimate variability on these time scales is large in magnitude. Results clarify our understanding of the dynamics that produce real-world pancontinental droughts while assessing the ability of models to accurately characterize future drought risks.
$\mathcal{L}^1$ limit solutions for control systems
Creators: name: Aronna, M. Soledad
name: Rampazzo, Franco
Publisher: name: arXiv
Year: 2014
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 34H05, 34A12, 93C10, 93C15

description: For a control Cauchy problem $$\dot x= {f}(t,x,u,v) +\sum_{α=1}^m g_α(x) \dot u_α,\quad x(a)=\bar x, $$ on an interval $[a,b]$, we propose a notion of limit solution $x,$ verifying the following properties: i) $x$ is defined for $\mathcal{L}^1$ (impulsive) inputs $u$ and for standard, bounded measurable, controls $v$; ii) in the commutative case (i.e. when $[g_α,g_β]\equiv 0,$ for all $α,β=1,...,m$), $x$ coincides with the solution one can obtain via the change of coordinates that makes the $g_α$ simultaneously constant; iii) $x$ subsumes former concepts of solution valid for the generic, noncommutative case. In particular, when $u$ has bounded variation, we investigate the relation between limit solutions and (single-valued) graph completion solutions. Furthermore, we prove consistency with the classical Carathéodory solution when $u$ and $x$ are absolutely continuous. Even though some specific problems are better addressed by means of special representations of the solutions, we believe that various theoretical issues call for a unified notion of trajectory. For instance, this is the case of optimal control problems, possibly with state and endpoint constraints, for which no extra assumptions (like e.g. coercivity, bounded variation, commutativity) are made in advance.
UNLEASHING VR'S FULL POTENTIAL - THE IMPACT OF 5G CONNECTIVITY
Creators: name: Brandl, Edenilson
Publisher: name: Zenodo
Year: 2023
Subjects: Virtual Reality (VR)
5G Connectivity
Systematic Review
Immersive Experiences
Technology Convergence
Transformative Potential
Practical Applications
Innovation Ecosystem
Human Interaction
Digital Content

description: In this comprehensive exploration, we delve into the transformative synergy between Virtual Reality (VR) and 5G connectivity. Conducting a systematic review of authoritative books, we focus on the intricate realms of VR technology, 5G networks, and their convergence. Rigorously selecting texts from reputable academic sources, our methodology ensures credibility and authenticity. The review illuminates the pivotal role of 5G in eliminating barriers to VR immersion, emphasizing its ultra-low latency and high bandwidth. Practical applications across industries, from healthcare to entertainment, showcase tangible transformations. The dynamic innovation ecosystem around VR and 5G indicates a wave of real-world innovation. These results signify a transformative force reshaping industries and human interaction with digital content. The article unfolds the practical applications and profound potential of the VR and 5G convergence, offering a glimpse into a future where boundaries of possibility continually expand.
In dieser umfassenden Untersuchung befassen wir uns mit der transformativen Synergie zwischen Virtual Reality (VR) und 5G-Konnektivität. Wir führen eine systematische Überprüfung maßgeblicher Bücher durch und konzentrieren uns auf die komplexen Bereiche der VR-Technologie, 5G-Netzwerke und deren Konvergenz. Durch die sorgfältige Auswahl von Texten aus seriösen akademischen Quellen gewährleistet unsere Methodik Glaubwürdigkeit und Authentizität. Der Test beleuchtet die entscheidende Rolle von 5G bei der Beseitigung von Hindernissen für das Eintauchen in die VR und betont seine extrem niedrige Latenz und hohe Bandbreite. Praktische Anwendungen in allen Branchen, vom Gesundheitswesen bis zur Unterhaltung, zeigen spürbare Veränderungen. Das dynamische Innovationsökosystem rund um VR und 5G deutet auf eine Welle realer Innovationen hin. Diese Ergebnisse verdeutlichen eine transformative Kraft, die Branchen und die menschliche Interaktion mit digitalen Inhalten neu gestaltet. Der Artikel entfaltet die praktischen Anwendungen und das tiefgreifende Potenzial der VR- und 5G-Konvergenz und bietet einen Einblick in eine Zukunft, in der sich die Grenzen der Möglichkeiten ständig erweitern.
A novel Bayesian approach to spectral function reconstruction
Creators: name: Burnier, Yannis
name: Rothkopf, Alexander
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a novel approach to the inference of spectral functions from Euclidean time correlator data that makes close contact with modern Bayesian concepts. Our method differs significantly from the maximum entropy method (MEM). A new set of axioms is postulated for the prior probability, leading to an improved expression, which is devoid of the asymptotically flat directions present in the Shanon-Jaynes entropy. Hyperparameters are integrated out explicitly, liberating us from the Gaussian approximations underlying the evidence approach of the MEM. We present a realistic test of our method in the context of the non-perturbative extraction of the heavy quark potential. Based on hard-thermal-loop correlator mock data, we establish firm requirements in the number of data points and their accuracy for a successful extraction of the potential from lattice QCD. An improved potential estimation from previously investigated quenched lattice QCD correlators is provided.
description: 4 pages, 4 figures
pyMSER -- An open-source library for automatic equilibration detection in molecular simulations
Creators: name: Oliveira, Felipe Lopes
name: Luan, Binquan
name: Esteves, Pierre Mothé
name: Steiner, Mathias
name: Ferreira, Rodrigo Neumann Barros
Publisher: name: arXiv
Year: 2024
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Computational Physics (physics.comp-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Automated molecular simulations are used extensively for predicting material properties. Typically, these simulations exhibit two regimes: a dynamic equilibration part, followed by a steady state. For extracting observable properties, the simulations must first reach a steady state so that thermodynamic averages can be taken. However, as equilibration depends on simulation conditions, predicting the optimal number of simulation steps a priori is impossible. Here, we demonstrate the application of the Marginal Standard Error Rule (MSER) for automatically identifying the optimal truncation point in Grand Canonical Monte Carlo (GCMC) simulations. This novel automatic procedure determines the point in which steady state is reached, ensuring that figures-of-merits are extracted in an objective, accurate, and reproducible fashion. In the case of GCMC simulations of gas adsorption in metal-organic frameworks, we find that this methodology reduces the computational cost by up to 90%. As MSER statistics are independent of the simulation method that creates the data, this library is, in principle, applicable to any time series analysis in which equilibration truncation is required. The open-source Python implementation of our method, pyMSER, is publicly available for reuse and validation at https://github.com/IBM/pymser.
description: 22 pages, 19 figures
MADANIYATLARARO MULOQOT VA O'ZBEK TILI TARAQQIYOTI
Creators: name: Yusupova Mubina O'tkirbek qizi Andijon davlat chet tillari instituti Xorijiy til va adabiyoti (ingliz tili) fakulteti 1-bosqich talabasi
Publisher: name: Zenodo
Year: 2023

description: Ushbu maqolada hozirgi kunda rivojlanib borayotgan chet tillarini o'rganish va boshqa madaniyat vakillari bilan bo'lgan muloqot yoritilgan. Shu bilan bir qatorda o'zbek tili taraqqiyotining yangi davri va ijtimoiy muammolari haqida ma'lumot berib o'tilgan.
Kalit so'zlar: jamiyat, kommunikatsiya, chet tili, globallashuv, davlat tili, sotsiolingvistika, milliy til.
Probabilistic representations as building blocks for higher-level vision
Creators: name: Chetverikov, Andrey
name: Kristjánsson, Árni
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Biological sciences

description: Current theories of perception suggest that the brain represents features of the world as probability distributions, but can such uncertain foundations provide the basis for everyday vision? Perceiving objects and scenes requires knowing not just how features (e.g., colors) are distributed but also where they are and which other features they are combined with. Using a Bayesian computational model, we recovered probabilistic representations used by human observers to search for odd stimuli among distractors. Importantly, we found that the brain integrates information between feature dimensions and spatial locations, leading to more precise representations compared to when information integration is not possible. We also uncovered representational asymmetries and biases, showing their spatial organization and explain how this structure argues against "summary statistics" accounts of visual representations. Our results confirm that probabilistically encoded visual features are bound with other features and to particular locations, providing a powerful demonstration of how probabilistic representations can be a foundation for higher-level vision.
description: Accepted for publication in Neurons, Behavior, Data Analysis and Theory (NBDT)
Biological Random Walks: multi-omics integration for disease gene prioritization
Creators: name: Gentili, Michele
name: Martini, Leonardo
name: Sponziello, Marialuisa
name: Becchetti, Luca
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: FOS: Biological sciences

description: Motivation: Over the past decade, network-based approaches have proven useful in identifying disease modules within the human interactome, often providing insights into key mechanisms and guiding the quest for therapeutic targets. This is all the more important, since experimental investigation of potential gene candidates is an expensive task, thus not always a feasible option. On the other hand, many sources of biological information exist beyond the interactome and an important research direction is the design of effective techniques for their integration. Results: In this work, we introduce the Biological Random Walks (BRW) approach for disease gene prioritization in the human interactome. The proposed framework leverages multiple biological sources within an integrated framework. We perform an extensive, comparative study of BRW's performance against well-established baselines. Availability and implementation: All code is publicly available and can be downloaded at \url{https://github.com/LeoM93/BiologicalRandomWalks}. We used publicly available datasets, details on their retrieval and preprocessing are provided in the supplementary material.
Thermal and non-thermal emission in the Cygnus X region
Creators: name: Xu, W. F.
name: Gao, X. Y.
name: Han, J. L.
name: Liu, F. S.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Radio continuum observations detect non-thermal synchrotron and thermal bremsstrahlung radiation. Separation of the two different emission components is crucial to study the properties of diffuse interstellar medium. The Cygnus X region is one of the most complex areas in the radio sky which contains a number of massive stars and HII regions on the diffuse thermal and non-thermal background. More supernova remnants are expected to be discovered. We aim to develop a method which can properly separate the non-thermal and thermal radio continuum emission and apply it to the Cygnus X region. The result can be used to study the properties of different emission components and search for new supernova remnants in the complex. Multi-frequency radio continuum data from large-scale surveys are used to develop a new component separation method. Spectral analysis is done pixel by pixel for the non-thermal synchrotron emission with a realistic spectral index distribution and a fixed spectral index of beta = -2.1 for the thermal bremsstrahlung emission. With the new method, we separate the non-thermal and thermal components of the Cygnus X region at an angular resolution of 9.5arcmin. The thermal emission component is found to comprise 75% of the total continuum emission at 6cm. Thermal diffuse emission, rather than the discrete HII regions, is found to be the major contributor to the entire thermal budget. A smooth non-thermal emission background of 100 mK Tb is found. We successfully make the large-extent known supernova remnants and the HII regions embedded in the complex standing out, but no new large SNRs brighter than Sigma_1GHz = 3.7 x 10^-21 W m^-2 Hz^-1 sr^-1 are found.
description: 9 pages, 5 figures, accepted by A&A. The quality of the figures is reduced due to file size limit of the website