cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
BSA-OMP: Beam-Split-Aware Orthogonal Matching Pursuit for THz Channel Estimation
Creators: name: Elbir, Ahmet M.
name: Chatzinotas, Symeon
Publisher: name: arXiv
Year: 2023
Subjects: subject: Signal Processing (eess.SP)
subject: Information Theory (cs.IT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Terahertz (THz)-band has been envisioned for the sixth generation wireless networks thanks to its ultra-wide bandwidth and very narrow beamwidth. Nevertheless, THz-band transmission faces several unique challenges, one of which is beam-split which occurs due to the usage of subcarrier-independent analog beamformers and causes the generated beams at different subcarriers split, and point to different directions. Unlike the prior works dealing with beam-split by employing additional complex hardware components, e.g., time-delayer networks, a beam-split-aware orthogonal matching pursuit (BSA-OMP) approach is introduced to efficiently estimate the THz channel and beamformer design without any additional hardware. Specifically, we design a BSA dictionary comprised of beam-split-corrected steering vectors which inherently include the effect of beam-split so that the proposed BSA-OMP solution automatically yields the beam-split-corrected physical channel directions. Numerical results demonstrate the superior performance of BSA-OMP approach against the existing state-of-the-art techniques.
description: Accepted Paper in IEEE Wireless Communications Letters
Searching for doubly charmed tetraquark candidates $T_{cc}$ and $T_{cc\bar{s}}$ in $B_c$ decays
Creators: name: Li, Yuan
name: He, Ying-Bo
name: Liu, Xiao-Hai
name: Chen, Baoyi
name: Ke, Hong-Wei
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In this work, we propose to search for the exotic doubly charmed meson $T_{cc}^+$ and its analog $T_{cc\bar{s}}^+$ in $B_c^+$ decays, which provide a good environment for the formation of the exotic state containing double charm quarks. Within the molecular scheme, the production of $T_{cc}^+$ and $T_{cc\bar{s}}^+$ through various rescattering processes with different intermediate states are investigated. For the moderate values of model parameters, the branching ratios of $B_c^+$ decaying into $T_{cc}^+ \bar{D}^{0}$, $T_{cc}^+ \bar{D}^{*0}$, $T_{cc\bar{s}}^+ \bar{D}^{0}$ and $T_{cc\bar{s}}^+ \bar{D}^{*0}$ are estimated to be of the order of $10^{-7}$, $10^{-5}$, $10^{-6}$ and $10^{-4}$, respectively, which may be tested by future experiments.
description: 9 pages, 8 figures
A Better Angle on Hadron Transverse Momentum Distributions at the EIC
Creators: name: Gao, Anjie
name: Michel, Johannes K. L.
name: Stewart, Iain W.
name: Sun, Zhiquan
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We propose an observable $q_*$ sensitive to transverse momentum dependence (TMD) in $e N \to e h X$, with $q_*/E_N$ defined purely by lab-frame angles. In 3D measurements of confinement and hadronization this resolves the crippling issue of accurately reconstructing small transverse momentum $P_{hT}$. We prove factorization for $\mathrm{d} σ_h / \mathrm{d}q_*$ for $q_*\ll Q$ with standard TMD functions, enabling $q_*$ to substitute for $P_{hT}$. A double-angle reconstruction method is given which is exact to all orders in QCD for $q_*\ll Q$. $q_*$ enables an order-of-magnitude improvement in the expected experimental resolution at the EIC.
description: 5 pages + 4 figures, 9 pages of supplemental material
Markov-modulated model for landing flow dynamics: An ordinal analysis validation
Creators: name: Olivares, Felipe
name: Zunino, Luciano
name: Zanin, Massimiliano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Air transportation is a complex system characterised by a plethora of interactions at multiple temporal and spatial scales; as a consequence, even simple dynamics like sequencing aircraft for landing can lead to the appearance of emergent behaviours, which are both difficult to control and detrimental to operational efficiency. We propose a model, based on a modulated Markov jitter, to represent ordinal pattern properties of real landing operations in European airports. The parameters of the model are tuned by minimising the distance between the probability distributions of ordinal patterns generated by the real and synthetic sequences, as estimated by the Permutation Jensen-Shannon Distance. We show that the correlation between consecutive hours in the landing flow changes between airports, and that it can be interpreted as a metric of efficiency. We further compare the dynamics pre and post COVID-19, showing how this has changed beyond what can be attributed to a simple reduction of traffic. We finally draw some operational conclusions, and discuss the applicability of these findings in a real operational environment.
description: 12 pages, 11 figures, 2 tables
Der Fall der Bilder. Zur Ikonologie negativer Vertikalität / La chute des images. Iconologie de la verticalité négative
Creators: name: Redaktion, Die
Publisher: name: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel
Year: 2017

description: -
description: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel, Jahresbericht / Rapport annuel 2015/2016
Investigating and Mitigating Failure Modes in Physics-informed Neural Networks (PINNs)
Creators: name: Basir, Shamsulhaq
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Numerical Analysis (math.NA)
subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: This paper explores the difficulties in solving partial differential equations (PDEs) using physics-informed neural networks (PINNs). PINNs use physics as a regularization term in the objective function. However, a drawback of this approach is the requirement for manual hyperparameter tuning, making it impractical in the absence of validation data or prior knowledge of the solution. Our investigations of the loss landscapes and backpropagated gradients in the presence of physics reveal that existing methods produce non-convex loss landscapes that are hard to navigate. Our findings demonstrate that high-order PDEs contaminate backpropagated gradients and hinder convergence. To address these challenges, we introduce a novel method that bypasses the calculation of high-order derivative operators and mitigates the contamination of backpropagated gradients. Consequently, we reduce the dimension of the search space and make learning PDEs with non-smooth solutions feasible. Our method also provides a mechanism to focus on complex regions of the domain. Besides, we present a dual unconstrained formulation based on Lagrange multiplier method to enforce equality constraints on the model's prediction, with adaptive and independent learning rates inspired by adaptive subgradient methods. We apply our approach to solve various linear and non-linear PDEs.
Le monde au temps des Surréalistes. Zentren, Peripherien und Itinerarien des surrealistischen Kunsthandels, 1925-1947 / Le monde au temps des surréalistes. Centres, périphéries et itinéraires du commerce de l'art surréaliste, 1925-1947
Creators: name: Redaktion, Die
Publisher: name: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel
Year: 2017

description: -
description: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel, Jahresbericht / Rapport annuel 2015/2016
Neutron scattering from fragmented frustrated magnets
Creators: name: Museur, F.
name: Lhotel, E.
name: Holdsworth, P. C. W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The fragmentation description is used to analyse calculated neutron scattering intensities from kagomé ice and spin ice systems. The longitudinal, transverse and harmonic fragments produce independent contributions to the neutron scattering intensity. This framework is used to analyse the ordering due to quantum fluctuations in the topologically constrained phase of kagomé ice and the monopole crystal phase of spin ice. Here, quantum fluctuations are restricted to the transverse fragment and they drive the system into a double-$q$ structure in which longitudinal and transverse fragments have a different ordering wave vector. The intensity reduction of the Bragg peaks for the transverse fragments, compared with known classical limits can be used as a diagnostic tool for quantum fluctuations. Published quantum Monte Carlo data for spin ice in a $[111]$ field are consistent with the proposed protocol.
description: 13 pages, 8 figures
Digital Humanities / Humanités numériques
Creators: name: Redaktion, Die
Publisher: name: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel
Year: 2017

description: -
description: Deutsches Forum für Kunstgeschichte (DFK Paris): Jahresbericht / Rapport annuel, Jahresbericht / Rapport annuel 2015/2016
Black Hole-Neutron Star Mergers with a Hot Nuclear Equation of State: Outflow and Neutrino-Cooled Disk for a Low-Mass, High-Spin Case
Creators: name: Deaton, M. Brett
name: Duez, Matthew D.
name: Foucart, Francois
name: O'Connor, Evan
name: Ott, Christian D.
name: Kidder, Lawrence E.
name: Muhlberger, Curran D.
name: Scheel, Mark A.
name: Szilagyi, Bela
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Neutrino emission significantly affects the evolution of the accretion tori formed in black hole-neutron star mergers. It removes energy from the disk, alters its composition, and provides a potential power source for a gamma-ray burst. To study these effects, simulations in general relativity with a hot microphysical equation of state and neutrino feedback are needed. We present the first such simulation, using a neutrino leakage scheme for cooling to capture the most essential effects and considering a moderate mass (1.4 M_{\odot} neutron star, 5.6 M_{\odot} black hole), high spin (black hole J/M^2=0.9) system with the K_0=220 MeV Lattimer-Swesty equation of state. We find that about 0.08 M_{\odot} of nuclear matter is ejected from the system, while another 0.3 M_{\odot} forms a hot, compact accretion disk. The primary effects of the escaping neutrinos are (i) to make the disk much denser and more compact, (ii) to cause the average electron fraction Y_e of the disk to rise to about 0.2 and then gradually decrease again, and (iii) to gradually cool the disk. The disk is initially hot (T~6 MeV) and luminous in neutrinos (L_ν~10^{54} erg s^{-1}), but the neutrino luminosity decreases by an order of magnitude over 50 ms of post-merger evolution.
description: Included erratum to the end of the article: affected average neutrino energy estimates
The Global Framework for Climate Services
Creators: name: Hewitt, Chris
name: Mason, Simon J.
name: Walland, David
Publisher: name: Columbia University
Year: 2012
Subjects: Climatic changes
Climate change mitigation
Climatic changes--Social aspects
Climatic changes--Risk management

description: There is a growing and urgent need to improve society’s resilience to climate-related hazards and better manage the risks and opportunities arising from climate variability and climate change.
Family dispute: do Type IIP supernova siblings agree on their distance?
Creators: name: Csörnyei, Géza
name: Vogl, Christian
name: Taubenberger, Stefan
name: Flörs, Andreas
name: Blondin, Stéphane
name: Cudmani, Maria Gabriela
name: Holas, Alexander
name: Kressierer, Sabrina
name: Leibundgut, Bruno
name: Hillebrandt, Wolfgang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Context: Type II supernovae provide a direct way to estimate distances through the expanding photosphere method, which is independent of the cosmic distance ladder. A recently introduced Gaussian process-based method allows for a fast and precise modelling of spectral time series, which puts accurate and computationally cheap Type II-based absolute distance determinations within reach. Aims: The goal of the paper is to assess the internal consistency of this new modelling technique coupled with the distance estimation empirically, using the spectral time series of supernova siblings, i.e. supernovae that exploded in the same host galaxy. Methods: We use a recently developed spectral emulator code, which is trained on \textsc{Tardis} radiative transfer models and is capable of a fast maximum likelihood parameter estimation and spectral fitting. After calculating the relevant physical parameters of supernovae we apply the expanding photosphere method to estimate their distances. Finally, we test the consistency of the obtained values by applying the formalism of Bayes factors. Results: The distances to four different host galaxies were estimated based on two supernovae in each. The distance estimates are not only consistent within the errors for each of the supernova sibling pairs, but in the case of two hosts they are precise to better than 5\%. Conclusions: Even though the literature data we used was not tailored for the requirements of our analysis, the agreement of the final estimates shows that the method is robust and is capable of inferring both precise and consistent distances. By using high-quality spectral time series, this method can provide precise distance estimates independent of the distance ladder, which are of high value for cosmology.
description: 20 pages, 20 figures, 6 tables, Accepted in A&A
Re-interpretations of an experiment on the back-action in a weak measurement
Creators: name: Nakamura, Kouji
name: Iinuma, Masataka
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Interpretations of an experiment on the back-action in a weak measurement in [M. Iinuma et al., New J. Phys. vol.13 (2011), 033041] are revisited. We show two different but essentially equivalent interpretations for this experiment along the original scenario of weak measurements proposed by Aharonov, Albert, and Vaidman. To do this, we introduce the notion of extended weak values which is associated not only with the states of the system but also the state of the measuring device. We also evaluate fluctuations in this experiment and found that an optimal measurement strength exists for a fixed polarization angle prepared as an initial state, at which fluctuations in measurement results vanish. The consistency of this evaluation with the experimental results is discussed.
description: 14 pages, 1 figure (v1); 8 pages, 1 figure, the style is changed. minor revision of Introduction, Summary and Discussion (v2); minor revision of Summary and discussions (v3); Minor revision of introduction and summary and discussion. Typos are corrected. Accepted for publication to Physical Review A
B. Schönegg: Der Tod des Seneca (Roman)
Creators: name: Giebel, Marion
Publisher: name: Forum Classicum
Year: 2017

description: Rezension zu: B. Schönegg: Der Tod des Seneca (Roman). Stuttgart (Reclam) 2001. 167 S.
description: Forum Classicum, Nr. 1 (2002): Forum Classicum
Continual Pre-training of Language Models
Creators: name: Ke, Zixuan
name: Shao, Yijia
name: Lin, Haowei
name: Konishi, Tatsuya
name: Kim, Gyuhak
name: Liu, Bing
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: Language models (LMs) have been instrumental for the rapid advance of natural language processing. This paper studies continual pre-training of LMs, in particular, continual domain-adaptive pre-training (or continual DAP-training). Existing research has shown that further pre-training an LM using a domain corpus to adapt the LM to the domain can improve the end-task performance in the domain. This paper proposes a novel method to continually DAP-train an LM with a sequence of unlabeled domain corpora to adapt the LM to these domains to improve their end-task performances. The key novelty of our method is a soft-masking mechanism that directly controls the update to the LM. A novel proxy is also proposed to preserve the general knowledge in the original LM. Additionally, it contrasts the representations of the previously learned domain knowledge (including the general knowledge in the pre-trained LM) and the knowledge from the current full network to achieve knowledge integration. The method not only overcomes catastrophic forgetting, but also achieves knowledge transfer to improve end-task performances. Empirical evaluation demonstrates the effectiveness of the proposed method.
description: https://github.com/UIC-Liu-Lab/ContinualLM
The angle of large values of $L$-functions
Creators: name: Hough, Bob
Publisher: name: arXiv
Year: 2013
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: We prove omega results for the central value of $L$-functions with the further condition that the angle is also constrained.
description: Accepted version. See the previous version for the twisted fourth moment calculation
The Alcock-Paczyński effect from Lyman-$α$ forest correlations: Analysis validation with synthetic data
Creators: name: Cuceu, Andrei
name: Font-Ribera, Andreu
name: Martini, Paul
name: Joachimi, Benjamin
name: Nadathur, Seshadri
name: Rich, James
name: González-Morales, Alma X.
name: Bourboux, Hélion du Mas des
name: Farr, James
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The three-dimensional distribution of the Ly$α$ forest has been extensively used to constrain cosmology through measurements of the baryon acoustic oscillations (BAO) scale. However, more cosmological information could be extracted from the full shapes of the Ly$α$ forest correlations through the Alcock-Paczyński (AP) effect. In this work, we prepare for a cosmological analysis of the full shape of the Ly$α$ forest correlations by studying synthetic data of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We use a set of one hundred eBOSS synthetic data sets in order to validate such an analysis. These mocks undergo the same analysis process as the real data. We perform a full-shape analysis on the mean of the correlation functions measured from the one hundred eBOSS realizations, and find that our model of the Ly$α$ correlations performs well on current data sets. We show that we are able to obtain an unbiased full-shape measurement of $D_M/D_H(z_\mathrm{eff})$, where $D_M$ is the transverse comoving distance, $D_H$ is the Hubble distance, and $z_\mathrm{eff}$ is the effective redshift of the measurement. We test the fit over a range of scales, and decide to use a minimum separation of $r_\mathrm{min}=25\ h^{-1}\text{Mpc}$. We also study and discuss the impact of the main contaminants affecting Ly$α$ forest correlations, and give recommendations on how to perform such analysis with real data. While the final eBOSS Ly$α$ BAO analysis measured $D_M/D_H(z_\mathrm{eff}=2.33)$ with $4\%$ statistical precision, a full-shape fit of the same correlations could provide a $\sim2\%$ measurement.
Building a framework for process-oriented evaluation of Regional Climate Outlook Forums
Creators: name: Gerlak, Andrea
name: Guido, Zack
name: Vaughan, Catherine
name: Rountree, Valerie
name: Greene, Christina
name: Liverman, Diana
name: Trotman, Adrian
name: Mahon, Roché
name: Cox, Shelly-Ann
name: Mason, Simon J.
name: Jacobs, Katharine
name: Buizer, James
name: Van Meerbeeck, Cedric
name: Baethgen, Walter E.
Publisher: name: Columbia University
Year: 2018
Subjects: Climatic changes
Long-range weather forecasting
Climatic changes--Research--International cooperation
Decision support systems--Evaluation

description: In many regions around the world, Regional Climate Outlook Forums (RCOFs) provide seasonal climate information and forecasts to decision-makers at regional and national levels. Despite having two decades of experience, the forums have not been systematically monitored or evaluated. To address this gap, and to better inform nascent and widespread efforts in climate services, the authors propose a process-oriented evaluation framework derived from literature on decision support and climate communication around the production and use of scientific information.The authors apply this framework to a case study of the Caribbean RCOF (CariCOF), where they have been engaged in a collaborative effort to integrate climate information and decision processes to enhance regional climate resilience. The authors’ examination of the CariCOF shows an evolution toward the use of more advanced and more diverse climate products, as well as greater awareness of user feedback. It also reveals shortfalls of the CariCOF, including a lack of diverse stakeholder participation, a need for better understanding of best practices to tailor information, undeveloped market research of climate products, insufficient experimentation and vetting of communication mechanisms, and the absence of a way to steward a diverse network of regional actors. The authors’ analysis also provides insight that allowed for improvements in the climate services framework to include mechanisms to respond to changing needs and conditions. The authors’ process-oriented framework can serve as a starting point for evaluating RCOFs and other organizations charged with the provision of climate services.
Perturbative Bottom-up Approach for Neutrino Mass Matrix in Light of Large θ_{13} and Role of Lightest Neutrino Mass
Creators: name: Dutta, Rupak
name: Ch, Upender
name: Giri, Anjan K.
name: Sahu, Narendra
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the role of lightest neutrino mass (m_0) in the neutrino mass matrix, defined in a flavor basis, through a bottom-up approach using the current neutrino oscillation data. We find that if m_0 < 10^{-3} eV, then the deviation δM_νin the neutrino mass matrix from a tree-level, say tribimaximal neutrino mass matrix, does not depend on m_0. As a result δM_ν's are exactly predicted in terms of the experimentally determined quantities such as solar and atmospheric mass squared differences and the mixing angles. On the other hand for m_0 \gsim 10^{-3} eV, δM_νstrongly depends on m_0 and hence can not be determined within the knowledge of oscillation parameters alone. In this limit, we provide an exponential parameterization for δM_νfor all values of m_0 such that it can factorize the m_0 dependency of δM_νfrom rest of the oscillation parameters. This helps us in finding δM_νas a function of the solar and atmospheric mass squared differences and the mixing angles for all values of m_0. We use this information to build up a model of neutrino masses and mixings in a top-down scenario which can predict large θ_{13} perturbatively.
description: 26 pages, 42 eps figures, revtex (references are added, more discussions are added in section-III)
Study on a Phase Space Representation of Quantum Theory
Creators: name: Ranaivoson, Tokiniaina
name: Andriambololona, Raoelina
name: Hanitriarivo, Rakotoson
name: Raboanary, Roland
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A study on a method for the establishment of a phase space representation of quantum theory is presented. The approach utilizes the properties of Gaussian distribution, the properties of Hermite polynomials, Fourier analysis and the current formulation of quantum mechanics which is based on the use of Hilbert space and linear operators theory. Phase space representation of quantum states and wave functions in phase space are introduced using properties of a set of functions called harmonic Gaussian functions. Then, new operators called dispersion operators are defined and identified as the operators which admit as eigenstates the basis states of the phase space representation. Generalization of the approach for multidimensional cases is shown. Examples of applications are given.
description: 10 pages
Constraints on the cosmic expansion rate at redshift 2.3 from the Lyman-$α$ forest
Creators: name: Cuceu, Andrei
name: Font-Ribera, Andreu
name: Nadathur, Seshadri
name: Joachimi, Benjamin
name: Martini, Paul
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We determine the product of the expansion rate and angular-diameter distance at redshift $z=2.3$ from the anisotropy of Lyman-$α$ (Ly$α$) forest correlations measured by the Sloan Digital Sky Survey (SDSS). Our result is the most precise from large-scale structure at $z>1$. In flat $Λ$CDM we determine the matter density to be $Ω_\mathrm{m}=0.36^{+0.03}_{-0.04}$ from Ly$α$ alone. This is a factor of two tighter than baryon acoustic oscillation results from the same data due to our use of a wide range of scales ($25
Improving CUR Matrix Decomposition and the Nyström Approximation via Adaptive Sampling
Creators: name: Wang, Shusen
name: Zhang, Zhihua
Publisher: name: arXiv
Year: 2013
Subjects: subject: Machine Learning (cs.LG)
subject: Numerical Analysis (math.NA)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: The CUR matrix decomposition and the Nyström approximation are two important low-rank matrix approximation techniques. The Nyström method approximates a symmetric positive semidefinite matrix in terms of a small number of its columns, while CUR approximates an arbitrary data matrix by a small number of its columns and rows. Thus, CUR decomposition can be regarded as an extension of the Nyström approximation. In this paper we establish a more general error bound for the adaptive column/row sampling algorithm, based on which we propose more accurate CUR and Nyström algorithms with expected relative-error bounds. The proposed CUR and Nyström algorithms also have low time complexity and can avoid maintaining the whole data matrix in RAM. In addition, we give theoretical analysis for the lower error bounds of the standard Nyström method and the ensemble Nyström method. The main theoretical results established in this paper are novel, and our analysis makes no special assumption on the data matrices.
Beyond the Unnameable
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2019
Subjects: Mentally ill--Commitment and detention
Mental illness--Social aspects
Social movements

description: Members of the Mental Patients Liberation Project are in studio with Bob taking calls. MPLP puts blame on civil liberties union for working with the psychiatric industry instead of supporting those institutionalized. Most callers disagree with members' stances, including a refusal to recognize any standards of mental health and idea that most patients in psychiatric wards are placed against their will
Probing the nature of the low state in the extreme ultraluminous X-ray pulsar NGC 5907 ULX1
Creators: name: Fuerst, F.
name: Walton, D. J.
name: Israel, G. L.
name: Bachetti, M.
name: Barret, D.
name: Brightman, M.
name: Earnshaw, H. P.
name: Fabian, A.
name: Heida, M.
name: Imbrogno, M.
name: Middleton, M. J.
name: Pinto, C.
name: Salvaterra, R.
name: Roberts, T. P.
name: Castillo, G. A. Rodríguez
name: Webb, N.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: NGC 5907 ULX1 is the most luminous ultra-luminous X-ray pulsar (ULXP) known to date, reaching luminosities in excess of 1e41 erg/s. The pulsar is known for its fast spin-up during the on-state. Here, we present a long-term monitoring of the X-ray flux and the pulse period between 2003-2022. We find that the source was in an off- or low-state between mid-2017 to mid-2020. During this state, our pulse period monitoring shows that the source had spun down considerably. We interpret this spin-down as likely being due to the propeller effect, whereby accretion onto the neutron star surface is inhibited. Using state-of-the-art accretion and torque models, we use the spin-up and spin-down episodes to constrain the magnetic field. For the spin-up episode, we find solutions for magnetic field strengths of either around 1e12G or 1e13G, however, the strong spin-down during the off-state seems only to be consistent with a very high magnetic field, namely, >1e13G. This is the first time a strong spin-down is seen during a low flux state in a ULXP. Based on the assumption that the source entered the propeller regime, this gives us the best estimate so far for the magnetic field of NGC 5907 ULX1.
description: 10 pages, 1 figure, accepted for publication in A&A
title: ΕΣΤΙΑ-ζωντας: Νέες φοιτητικές εστίες στο T.U.C.
Creators: name: Προκοπη Ανδριαννα-Κωνσταντινα
Publisher: name: Technical University of Crete
Year: 2015

description: Η διπλωματική εργασία αφορά τον σχεδιασμό φοιτητικών εστιών στο Πολυτεχνείο Κρήτης, δυναμικότητας 260 φοιτητών. Οι νέες φοιτητικές εστίες τοποθετούνται στους χώρους της Πολυτεχνειούπολης, έξω από την πόλη των Χανίων και κοντά στον οικισμό των Κουνουπιδιανών. Στόχος της εργασίας, αποτελεί ο συνδυασμός της ανάγκης για στέγαση και της ανάγκης για κοινωνικότητα και κοινωνική συναναστροφή μεταξύ των φοιτητών. Επίσης, διερευνάται χωρικά η ανεξάρτητη μονάδα μέσα στο σύνολο και η ταυτόχρονη αυτονομία και συνάθροιση που δημιουργούν ευνοϊκές συνθήκες ζωής.
Kähler-Einstein metrics on stable varieties and log canonical pairs
Creators: name: Berman, Robert J.
name: Guenancia, Henri
Publisher: name: arXiv
Year: 2013
Subjects: subject: Complex Variables (math.CV)
subject: Algebraic Geometry (math.AG)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Let $X$ be a canonically polarized variety, i.e. a complex projective variety such that its canonical class $K_{X}$ defines an ample $\Q-$line bundle, and satisfying the conditions $G_1$ and $S_2$. Our main result says that $X$ admits a Kähler-Einstein metric iff $X$ has semi-log canonical singularities i.e. iff $X$ is a stable variety in the sense of Kollár-Shepherd-Barron and Alexeev (whose moduli spaces are known to be compact). By definition a Kähler-Einstein metric in this singular context simply means a Kähler-Einstein on the regular locus of $X$ with volume equal to the algebraic volume of $K_{X},$ i.e. the top intersection number of $K_{X}.$ We also show that such a metric is uniquely determined and extends to define a canonical positive current in $c_{1}(K_{X}).$ Combined with recent results of Odaka our main result shows that $X$ admits a Kähler-Einstein metric iff $X$ is K-stable, which thus confirms the Yau-Tian-Donaldson conjecture in this general setting of (possibly singular) canonically polarized varieties. More generally, our results are shown to hold in the setting of log minimal varieties and they also generalize some prior results concerning Kähler-Einstein metrics on quasi-projective varieties.
description: 46 pages; v2: published version
Exploring maverick top partner decays at the LHC
Creators: name: Verma, Shivam
name: Biswas, Sanjoy
name: Chatterjee, Anirban
name: Ganguly, Joy
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In this work, we have considered an extension of the standard model (SM) with a $SU(2)_L$ singlet vectorlike quark (VLQ) with electric charge $Q=+2/3$. The model also contains an additional local $U(1)_d$ symmetry group and the corresponding gauge boson is the dark photon. The VLQ is charged while all the SM particles are neutral under the new $U(1)_d$ gauge group. Even though in this model the VLQ possesses many properties qualitatively similar to that of the traditional top partner ($T_p$), there are some compelling differences as well. In particular, its branching ratio to the traditional modes ($T_p \to bW, tZ, th$) are suppressed which in turn helps to evade many of the existing bound, mainly coming from the LHC experiments. In an earlier work, such a VLQ is referred to as ``maverick top partner". It has been shown that the top partner in this model predominantly decays to a top quark and a dark photon/dark higgs pair ($T_p \to tγ_d ,~th_d$) over a large region of the parameter space. The dark photon can be made invisible and consequently, it gives rise to the missing transverse energy ($\not\!\!{E} _{T}$) signature at the LHC detector. We have mainly focused on the LHC signatures and future prospects of such top partners. In particular, we have studied the $t\bar{t}+\not\!\!{E}_{T}$ and $t+\not\!\!{E}_{T}$ signatures in the context of the LHC via pair and single productions of the top partner, respectively at 13 and 14 TeV LHC center of mass energies assuming that the dark photon either decays into an invisible mode or it is invisible at the length scale of the detector. We have shown that one can exclude $\sinθ_L \sim 0.025$ (0.05) for $m_{_{T_p}} \leq $ 2.0 (2.6) TeV at $\sqrt{s}=14$ TeV with an integrated luminosity of 3 ab$^{-1}$ using the single top partner production channel.
description: 31 pages, 18 figures, 12 tables. Additional background contributions has been added and Fig. 16 has been updated with mass dependent bound. Matches with version published in Phys. Rev. D
Generalized scale functions for spectrally negative Lévy processes
Creators: name: Contreras, Jesús
name: Rivero, Victor
Publisher: name: arXiv
Year: 2022
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J99, 60G51

description: For a spectrally negative Lévy process, scale functions appear in the solution of two-sided exit problems, and in particular in relation with the Laplace transform of the first time it exits a closed interval. In this paper, we consider the Laplace transform of more general functionals, which can depend simultaneously on the values of the process and its supremum up to the exit time. These quantities will be expressed in terms of generalized scale functions, which can be defined using excursion theory. In the case the functional does not depend on the supremum, these scale functions coincide with the ones found on the literature, and therefore the results in this work are an extension of them.
description: 22 pages
Scalaron Decay in Perturbative Quantum Gravity
Creators: name: Latosh, Boris N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A certain quadratic gravity model provides a successfully inflationary scenario. The inflation is driven by the new scalar degree of freedom called scalaron. After the end of inflation the scalaron decays in matter and dark matter degrees of freedom reheating the Universe. We study new channels by which the scalaron can transfer energy to the matter sector. These channels are annihilation and decay via intermediate graviton states. Results are obtained within perturbative quantum gravity. In the heavy scalaron limit only scalar particles are produced by the annihilation channel. Scalaron decays in all types of particles are allowed. In the light scalaron limit decay channel is strongly suppressed. Boson production via the annihilation channel is expected to be dominant at the early stages of reheating, while fermion production will dominate later stages.
title: Ενοποίηση της Αθηναϊκής Τριλογίας με την πλατεία Κλαυθμώνος, την οδό Κοραή και το Πνευματικό κέντρο του Δήμου Αθηναίων: δημιουργία ενός νέου πολυλειτουργικού συνόλου για την αναζωογόνηση του κέντρου των Αθηνών
Creators: name: Τριποδακη Ιολη-Ειρηνη
Publisher: name: Technical University of Crete
Year: 2015

description: Η παρούσα διπλωματική εργασία έχει ως θέμα την ανάπλαση της περιοχής που εκτείνεται από την πλατεία Κλαυθμώνος μέχρι και το Πνευματικό Κέντρο του δήμου των Αθηνών και αποσκοπεί στην αναζωογόνηση του κέντρου της πρωτεύουσας δημιουργώντας ένα νέο πολυλειτουργικό πυρήνα στην πόλη.
Statefinder hierarchy of bimetric and galileon models for concordance cosmology
Creators: name: Myrzakulov, R.
name: Shahalam, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, we use Statefinder hierarchy method to distinguish between bimetric theory of massive gravity, galileon modified gravity and DGP models applied to late time expansion of the universe. We also carry out comparison between bimetric and DGP models using Statefinder pairs {r, s} and {r, q}. We show that statefinder diagnostic can differentiate between ΛCDM and above mentioned cosmological models of dark energy, and finally show that Statefinder S2 is an excellent discriminant of ΛCDM and modified gravity models.
description: 15 pages, 8 figures, LaTeX, some texts, Refs. added, to appear in JCAP
Estimating the longitudinal magnetic field in the chromosphere of quiet-Sun magnetic concentrations
Creators: name: Pozuelo, S. Esteban
name: Ramos, A. Asensio
name: Rodríguez, J. de la Cruz
name: Bueno, J. Trujillo
name: González, M. J. Martínez
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Details of the magnetic field in the quiet Sun chromosphere are key to our understanding of essential aspects of the solar atmosphere. We aim to determine the longitudinal magnetic field component (B_lon) of quiet Sun regions depending on their size. We estimated B_lon by applying the weak-field approximation (WFA) to high-spatial-resolution Ca II 854.2 nm data taken with the Swedish 1m Solar Telescope. Specifically, we analyzed the estimates inferred for different spectral ranges using the data at the original cadence and temporally integrated signals. The longitudinal magnetic field in each considered plasma structure correlates with its size. Using a spectral range restricted to the line core leads to chromospheric longitudinal fields varying from 50 G at the edges to 150-500 G at the center of the structure. These values increase as the spectral range widens due to the photospheric contribution. However, the difference between this contribution and the chromospheric one is not uniform for all structures. Small and medium-sized concentrations show a steeper height gradient in B_lon compared to their chromospheric values, so estimates for wider ranges are less trustworthy. Signal addition does not alleviate this situation as the height gradients in B_lon are consistent with time. Finally, despite the amplified noise levels that deconvolving processes may cause, data restored with the destretching technique show similar results, though are affected by smearing. We obtained B_lon estimates similar to those previously found, except for large concentrations and wide spectral ranges. In addition, we report a correlation between the height variation of B_lon compared to the chromospheric estimates and the concentration size. This correlation affects the difference between the photospheric and chromospheric magnetic flux values and the reliability of the estimates for wider spectral ranges.
description: 14 pages, 14 figures. Accepted for publication in Astronomy & Astrophysics; abstract has been abridged
A Conversation with Edie Windsor
Creators: name: Goldberg, Suzanne B.
name: Gomez, Madeline M.
name: Chesley, Andrew
Publisher: name: Columbia University
Year: 2015
Subjects: subject: Gay rights
subject: Civil rights
subject: Same-sex marriage
subject: Law
subject: FOS: Law

description: Suzanne Goldberg ISGI: It is not often that a law school gets to welcome a rock star. But in our world, Edie Windsor is a rock star. She is one of the major civil rights plaintiffs of our lifetime, whose lawsuit challenged-and triumphed over-the federal Defense of Marriage Act. Her victory in that suit has been vital to changing the landscape of marriage equality for all Americans. It is a tremendous honor, Edie, to have you here at Columbia Law School, and we welcome you.
ROAD-R: The Autonomous Driving Dataset with Logical Requirements
Creators: name: Giunchiglia, Eleonora
name: Stoian, Mihaela Cătălina
name: Khan, Salman
name: Cuzzolin, Fabio
name: Lukasiewicz, Thomas
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Neural networks have proven to be very powerful at computer vision tasks. However, they often exhibit unexpected behaviours, violating known requirements expressing background knowledge. This calls for models (i) able to learn from the requirements, and (ii) guaranteed to be compliant with the requirements themselves. Unfortunately, the development of such models is hampered by the lack of datasets equipped with formally specified requirements. In this paper, we introduce the ROad event Awareness Dataset with logical Requirements (ROAD-R), the first publicly available dataset for autonomous driving with requirements expressed as logical constraints. Given ROAD-R, we show that current state-of-the-art models often violate its logical constraints, and that it is possible to exploit them to create models that (i) have a better performance, and (ii) are guaranteed to be compliant with the requirements themselves.
Differential equations and logarithmic intertwining operators for strongly graded vertex algebras
Creators: name: Yang, Jinwei
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Algebra (math.QA)
subject: Analysis of PDEs (math.AP)
subject: Category Theory (math.CT)
subject: FOS: Mathematics
subject: 17B69, 06B15, 18D10, 35A01

description: We derive certain systems of differential equations for matrix elements of products and iterates of logarithmic intertwining operators among strongly graded generalized modules for a strongly graded conformal vertex algebra under suitable assumptions. Using these systems of differential equations, we verify the convergence and extension property needed in the logarithmic tensor category theory for such strongly graded generalized modules developed by Huang, Lepowsky and Zhang.
description: 26 pages. For the sake of readability, I quote certain necessary technical definitions from earlier work of Y.-Z. Huang, J. Lepowsky and L. Zhang [arXiv:0710.2687, arXiv:1012.4193, arXiv:math/0609833]
SimplyE: Current Efforts and Future Plans
Creators: name: Cartolano, Robert T.
name: English, James
name: Peterson, Christine
Publisher: name: Columbia University
Year: 2020
Subjects: Electronic books
Libraries
Digital libraries

description: SimplyE continues to gain momentum across public and academic libraries. New efforts are underway to better understand the needs of ebook readers and improve the system to meet the needs of institutions. Learn about recent accomplishments, current efforts and future plans to improve SimplyE and expand its use in libraries.
Debris Disk Color with the Hubble Space Telescope
Creators: name: Ren, Bin B.
name: Rebollido, Isabel
name: Choquet, Élodie
name: Zhou, Wen-Han
name: Perrin, Marshall D.
name: Schneider, Glenn
name: Milli, Julien
name: Wolff, Schuyler G.
name: Chen, Christine H.
name: Debes, John H.
name: Hagan, J. Brendan
name: Hines, Dean C.
name: Millar-Blanchaer, Maxwell A.
name: Pueyo, Laurent
name: Roberge, Aki
name: Serabyn, Eugene
name: Soummer, Rémi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Multi-wavelength scattered light imaging of debris disks may inform dust properties including typical size and mineral composition. Existing studies have investigated a small set of individual systems across a variety of imaging instruments and filters, calling for uniform comparison studies to systematically investigate dust properties. We obtain the surface brightness of dust particles in debris disks by post-processing coronagraphic imaging observations, and compare the multi-wavelength reflectance of dust. For a sample of resolved debris disks, we perform a systematic analysis on the reflectance properties of their birth rings. We reduced the visible and near-infrared images of 23 debris disk systems hosted by A through M stars using two coronagraphs onboard the Hubble Space Telescope: the STIS instrument observations centering at 0.58 $μ$m, and the NICMOS instrument at 1.12 $μ$m or 1.60 $μ$m. For proper recovery of debris disks, we used classical reference differential imaging for STIS, and adopted non-negative matrix factorization with forward modeling for NICMOS. By dividing disk signals by stellar signals to take into account of intrinsic stellar color effects, we systematically obtained and compared the reflectance of debris birth rings at ~90 deg scattering angle. Debris birth rings typically exhibit a blue color at ~90 deg scattering angle. As the stellar luminosity increases, the color tends to be more neutral. A likely L-shaped color-albedo distribution indicates a clustering of scatterer properties. The observed color trend correlates with the expected blow-out size of dust particles. The color-albedo clustering likely suggests different populations of dust in these systems. More detailed radiative transfer models with realistic dust morphology will contribute to explaining the observed color and color-albedo distribution of debris systems.
description: 17 pages, 8 figures, 3 tables. A&A accepted