cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Generalized Killing spinors on spheres
Creators: name: Moroianu, Andrei
name: Semmelmann, Uwe
Publisher: name: arXiv
Year: 2013
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53C25, 53C27, 53C40

description: We study generalized Killing spinors on round spheres $\mathbb{S}^n$. We show that on the standard sphere $\mathbb{S}^8$ any generalized Killing spinor has to be an ordinary Killing spinor. Moreover we classify generalized Killing spinors on $\mathbb{S}^n$ whose associated symmetric endomorphism has at most two eigenvalues and recover in particular Agricola--Friedrich's canonical spinor on 3-Sasakian manifolds of dimension 7. Finally we show that it is not possible to deform Killing spinors on standard spheres into genuine generalized Killing spinors.
description: 16 pages; new version filling a gap in the proof of Lemma 4.1 which was brought to our attention by Stanislav Wiechmann
Sonnenfleckenzeichnung Nr. 194.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 10.08.1999, 09:30, erstellt von Edy Alge
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Point-to-point distance in first passage percolation on (tree) x Z
Creators: name: Benjamini, Itai
name: Maillard, Pascal
Publisher: name: arXiv
Year: 2013
Subjects: subject: Probability (math.PR)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics

description: We consider first passage percolation (FPP) on T_d x Z, where T_d is the d-regular tree (d>=3). It is shown that for a fixed vertex v in the tree, the fluctuation of the distance in the FPP metric between the points (v,0) and (v,n) is of the order of at most log n. We conjecture that the real fluctuations are of order 1 and explain why.
description: 4 pages, published version
Imbalanced Multi-label Classification for Business-related Text with Moderately Large Label Spaces
Creators: name: Arslan, Muhammad
name: Cruz, Christophe
Publisher: name: arXiv
Year: 2023
Subjects: subject: Information Retrieval (cs.IR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: In this study, we compared the performance of four different methods for multi label text classification using a specific imbalanced business dataset. The four methods we evaluated were fine tuned BERT, Binary Relevance, Classifier Chains, and Label Powerset. The results show that fine tuned BERT outperforms the other three methods by a significant margin, achieving high values of accuracy, F1 Score, Precision, and Recall. Binary Relevance also performs well on this dataset, while Classifier Chains and Label Powerset demonstrate relatively poor performance. These findings highlight the effectiveness of fine tuned BERT for multi label text classification tasks, and suggest that it may be a useful tool for businesses seeking to analyze complex and multifaceted texts.
Sonnenfleckenzeichnung Nr. 199.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 16.08.1999, 08:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 289.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 16.12.1999, 10:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
A quantitative description of comet 67P's dust and gas production remains enigmatic
Creators: name: Bischoff, Dorothea
name: Schuckart, Christian
name: Attree, Nicholas
name: Gundlach, Bastian
name: Blum, Jürgen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The mechanism of dust emission from a cometary nucleus is still an open question and thermophysical models have problems reproducing outgassing and dust productions rates simultaneously. In this study, we investigate the capabilities of a rather simple thermophysical model to match observations from Rosetta instruments at comet 67P/Churyumov-Gerasimenko and the influence of model variations. We assume a macro-porous surface structure composed of pebbles and investigate the influence of different model assumptions. Besides the scenario in which dust layers are ejected when the vapour pressure overcomes the tensile strength, we use artificial ejection mechanisms, depending on ice-depletion of layers. We find that dust activity following the pressure criterion is only possible for reduced tensile strength values or reduced gas diffusivity and is inconsistent with observed outgassing rates, because activity is driven by CO$_2$. Only when we assume that dust activity is triggered when the layer is completely depleted in H$_2$O, the ratio of CO$_2$ to H$_2$O outgassing rates is in the expected order of magnitude. However, the dust-to-H$_2$O ratio is never reproduced. Only with decreased gas diffusivity, the slope of the H$_2$O outgassing rate is matched, however absolute values are too low. To investigate maximum reachable pressures, we adapted our model equivalent to a gas-impermeable dust structure. Here, pressures exceeding the tensile strength by orders of magnitude are possible. Maximum activity distances of $3.1 \,\mathrm{au}$, $8.2 \,\mathrm{au}$, and $74 \,\mathrm{au}$ were estimated for H$_2$O-, CO$_2$-, and CO-driven activity of $1 \,\mathrm{cm}$-sized dust, respectively. In conclusion, the mechanism behind dust emission remains unclear.
description: Accepted for publication in MNRAS
Moser's Shadow Problem
Creators: name: Lagarias, Jeffrey C.
name: Luo, Yusheng
name: Padrol, Arnau
Publisher: name: arXiv
Year: 2013
Subjects: subject: Metric Geometry (math.MG)
subject: Computational Geometry (cs.CG)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: Primary: 52B10, Secondary: 51N15, 65D18, 68U05, 90C05

description: Moser's shadow problem asks to estimate the shadow function $\mathfrak{s}_b(n)$, which is the largest number such that for each bounded convex polyhedron $P$ with $n$ vertices in $3$-space there is some direction ${\bf v}$ (depending on $P$) such that, when illuminated by parallel light rays from infinity in direction ${\bf v}$, the polyhedron casts a shadow having at least $\mathfrak{s}_b(n)$ vertices. A general version of the problem allows unbounded polyhedra as well, and has associated shadow function $\mathfrak{s}_u(n)$. This paper presents correct order of magnitude asymptotic bounds on these functions. The bounded case has answer $\mathfrak{s}_b(n) = Θ\big( \log (n)/ (\log(\log (n))\big$. The unbounded shadow problem is shown to have the different asymptotic growth rate $\mathfrak{s}_u(n) = Θ\big(1\big)$. Results on the bounded shadow problem follow from 1989 work of Chazelle, Edelsbrunner and Guibas on the (bounded) silhouette span number $\mathfrak{s}_b^{\ast}(n)$, defined analogously but with arbitrary light sources. We complete the picture by showing that the unbounded silhouette span number $\mathfrak{s}_u^{\ast}(n)$ grows as $Θ\big( \log (n)/ (\log(\log (n))\big)$.
description: v5, 25 pages, additional result added for unbounded silhouette span
Arratia flow with drift and the Trotter formula for Brownian web
Creators: name: Dorogovtsev, A. A.
name: Vovchanskii, M. B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: An analog of the Trotter formula for the Arratia flow is presented. Perturbations of the Brownian web by mappings associated with an ordinary differential equation with a smooth right part are considered and proved to be convergent exclusively in the weak sense. The flow obtained as a limit is the Arratia flow with drift.
description: 20 pages
Sonnenfleckenzeichnung Nr. 47.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 23.02.1999, 08:45, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 284.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 07.12.1999, 09:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 5.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 07.01.1999, 09:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 216.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 02.09.1999, 07:30, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Massive galaxy formation caught in action at z~5 with JWST
Creators: name: Jin, Shuowen
name: Sillassen, Nikolaj B.
name: Magdis, Georgios E.
name: Vijayan, Aswin P.
name: Brammer, Gabriel B.
name: Kokorev, Vasily
name: Weaver, John R.
name: Gobat, Raphael
name: Giménez-Arteaga, Clara
name: Valentino, Francesco
name: Brinch, Malte
name: Gómez-Guijarro, Carlos
name: Shuntov, Marko
name: Toft, Sune
name: Greve, Thomas R.
name: Sese, David Blanquez
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We report the discovery of a compact group of galaxies, CGG-z5, at z~5.2 in the EGS field covered by the JWST/CEERS survey. CGG-z5 was selected as the highest overdensity of galaxies at z>2 in recent JWST public surveys and it consists of six candidate members lying within a projected area of $1.5"\times3"$ (10$\times$20~kpc$^2$). All group members are HST/F435W and HST/F606W dropouts while securely detected in the JWST/NIRCam bands, yielding a narrow range of robust photometric redshifts $5.011$) at z~1. This implies that CGG-z5 could be a "proto-massive galaxy" captured during a short-lived phase of massive galaxy formation.
description: Published in A&A Letter
Sonnenfleckenzeichnung Nr. 121.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 23.05.1999, 10:00, erstellt von Andrea Manna
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 81.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 02.04.1999, 07:30, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Sonnenfleckenzeichnung Nr. 229.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 15.09.1999, 07:30, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Quality of Service Based Radar Resource Management for Navigation and Positioning
Creators: name: Müller, Tobias
name: Durst, Sebastian
name: Marquardt, Pascal
name: Brüggenwirth, Stefan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In hostile environments, GNSS is a potentially unreliable solution for self-localization and navigation. Many systems only use an IMU as a backup system, resulting in integration errors which can dramatically increase during mission execution. We suggest using a fighter radar to illuminate satellites with known trajectories to enhance the self-localization information. This technique is time-consuming and resource-demanding but necessary as other tasks depend on the self-localization accuracy. Therefore an adaption of classical resource management frameworks is required. We propose a quality of service based resource manager with capabilities to account for inter-task dependencies to optimize the self-localization update strategy. Our results show that this leads to adaptive navigation update strategies, mastering the trade-off between self-localization and the requirements of other tasks.
description: 8 pages, 9 figures
Framed M-branes, corners, and topological invariants
Creators: name: Sati, Hisham
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Algebraic Topology (math.AT)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We uncover and highlight relations between the M-branes in M-theory and various topological invariants: the Hopf invariant over $\mathbb{Q}$, $\mathbb{Z}$ and $\mathbb{Z}_2$, the Kervaire invariant, the $f$-invariant, and the $ν$-invariant. This requires either a framing or a corner structure. The canonical framing provides a minimum for the classical action and the change of framing encodes the structure of the action and possible anomalies. We characterize the flux quantization condition on the C-field and the topological action of the M5-brane via the Hopf invariant, and the dual of the C-field as (a refinement of) an element of Hopf invariant two. In the signature formulation, the contribution to the M-brane effective action is given by the Maslov index of the corner. The Kervaire invariant implies that the effective action of the M5-brane is quadratic. Our study leads to viewing the self-dual string, which is the boundary of the M2-brane on the M5-brane worldvolume, as a string theory in the sense of cobordism of manifolds with corners. We show that the dynamics of the C-field and its dual are encoded in unified way in the 4-sphere, which suggests the corresponding spectrum as the generalized cohomology theory describing the fields. The effective action of the corner is captured by the $f$-invariant, which is an invariant at chromatic level two. Finally, considering M-theory on manifolds with G_2 holonomy we show that the canonical ${\rm G}_2$ structure minimizes the topological part of the M5-brane action. This is done via the $ν$-invariant and a variant that we introduce related to the one-loop polynomial.
description: 33 pages, minor revisions, updated context and references, published version
Sonnenfleckenzeichnung Nr. 139.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 12.06.1999, 07:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
A comparison of vakonomic and nonholonomic dynamics with applications to non-invariant Chaplygin systems
Creators: name: Jóźwikowski, Michał
name: Respondek, Witold
Publisher: name: arXiv
Year: 2013
Subjects: subject: Differential Geometry (math.DG)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 49S05, 70H45, 70H30, 70G45

description: We study relations between vakonomically and nonholonomically constrained Lagrangian dynamics for the same set of linear constraints. The basic idea is to compare both situations at the level of variational principles, not equations of motion as has been done so far. The method seems to be quite powerful and effective. In particular, it allows to derive, interpret and generalize many known results on non-Abelian Chaplygin systems. We apply it also to a class of systems on Lie groups with a left-invariant constraints distribution. Concrete examples of the unicycle in a potential field, the two-wheeled carriage and the generalized Heisenberg system are discussed.
description: 42 pages, 4 figures, minor revision, submitted version
Monopole and instanton effects on connected and disconnected correlations for scalar density
Creators: name: Hasegawa, Masayasu
Publisher: name: arXiv
Year: 2022
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: This study investigates the effects on the connected and disconnected correlations for the scalar density that are induced by created monopoles and instantons in the QCD vacuum. To reveal the effects, we add a monopole and anti-monopole pair in the gauge field configurations in \textit{SU}(3) by applying the monopole creation operator to the vacuum. We vary the magnetic charges of the monopole and anti-monopole and increase the number of monopoles and anti-monopoles in the configurations. The Dirac operator of overlap fermions preserves the exact chiral symmetry in lattice gauge theory and exact zero-modes exist in its spectrum. The eigenvalues and eigenvectors of the overlap Dirac operator have been calculated using these configurations, and the numbers of instantons and anti-instantons which are created by these additional monopoles and anti-monopoles have been estimated from the numbers of topological charges in our previous studies. In this study, we demonstrate the preliminary results that instantons and monopoles influence the masses that are evaluated from the connected and disconnected correlation functions for the scalar density using low-lying eigenvalues and eigenvectors of the overlap Dirac operator.
description: This report is a contribution to the proceedings of "the 6th International Conference on Particle Physics and Astrophysics'' and accepted for publication in Physics of Atomic Nuclei. This report contains 5 figures and 5 tables on 12 pages
$G_2$-instantons on twisted connected sums
Creators: name: Earp, Henrique Sá
name: Walpuski, Thomas
Publisher: name: arXiv
Year: 2013
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: We introduce a method to construct $G_2$-instantons over compact $G_2$-manifolds arising as the twisted connected sum of a matching pair of building blocks [Kov03,KL11,CHNP12]. Our construction is based on gluing $G_2$-instantons obtained from holomorphic bundles over the building blocks via the first named author's work [SE11]. We require natural compatibility and transversality conditions which can be interpreted in terms of certain Lagrangian subspaces of a moduli space of stable bundles on a K3 surface.
description: v2: published version
Selective covering properties of product spaces, II: gamma spaces
Creators: name: Miller, Arnold W.
name: Tsaban, Boaz
name: Zdomskyy, Lyubomyr
Publisher: name: arXiv
Year: 2013
Subjects: subject: Logic (math.LO)
subject: Functional Analysis (math.FA)
subject: General Topology (math.GN)
subject: FOS: Mathematics

description: We study productive properties of gamma spaces, and their relation to other, classic and modern, selective covering properties. Among other things, we prove the following results: 1. Solving a problem of F. Jordan, we show that for every unbounded tower set of reals X of cardinality aleph_1, the space Cp(X) is productively FU. In particular, the set X is productively gamma. 2. Solving problems of Scheepers and Weiss, and proving a conjecture of Babinkostova-Scheepers, we prove that, assuming CH, there are gamma spaces whose product is not even Menger. 3. Solving a problem of Scheepers-Tall, we show that the properties gamma and Gerlits--Nagy (*) are preserved by Cohen forcing. Moreover, every Hurewicz space that Remains Hurewicz in a Cohen extension must be Rothberger (and thus (*)). We apply our results to solve a large number of additional problems, and use Arhangel'skii duality to obtain results concerning local properties of function spaces and countable topological groups.
description: Minor errors corrected
Sonnenfleckenzeichnung Nr. 3.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 05.01.1999, 08:30, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Linearized eigenvalues for a free boundary problem modeling two-phase tumor growth
Creators: name: Cui, Shangbin
name: Zheng, Jiayue
Publisher: name: arXiv
Year: 2013
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: In this paper we study a linearized eigenvalue problem derived from a a free boundary problem modeling the growth of a tumor containing two species of cells: proliferating cells and quiescent cells. The reduced form of this eigenvalue problem is a $2$-system of a first-order nonlocal singular differential-integral equation in a ball coupled by a third-order elliptic pseudo-differential equation in the unit sphere. The singularity joined with non-localness of the first-order equation causes the main difficulty of this problem. By using Fourier expansion via a basis of spherical harmonic functions and some techniques for solving singular differential integral equations developed in some previous literature, we prove that there exists a null sequence $\{γ_k\}_{k=2}^{\infty}$ for the surface tension coefficient $γ$, with each of them being an eigenvalue of the linearized problem, i.e., if $γ=γ_k$ for some $k\geq 2$ then the linearized problem has extra nontrivial solutions besides the standard nontrivial solutions, and if $γ\neqγ_k$ for all $k\geq 2$ then the linearized problem does not have other nontrivial solutions than the standard nontrivial solutions. Invertibility of some linear operators related to the linearized problem in suitable function spaces is also studied.
description: 27 pages
Tape #10: compilation of Bella Abzug commenting on CNN about various topics
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2021
Subjects: Politics and government

description: Japanese Americans 3/2/198?, Cut military spending, Women and Reagan, 3/9/8[?]; Freeze in Congress, Satellite sales, Women and Budget, Surveillance, Argentina, 3/11/81; Hatch, Central America, Space invaders, 3/29/83; Affirmation, Nicaragua, Campaign cost, Product liability, 4/6/87
Accurate reduced models for the pH oscillations in the urea-urease reaction confined to giant lipid vesicles
Creators: name: Straube, Arthur V.
name: Winkelmann, Stefanie
name: Höfling, Felix
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: This theoretical study concerns a pH oscillator based on the urea-urease reaction confined to giant lipid vesicles. Under suitable conditions, differential transport of urea and hydrogen ion across the unilamellar vesicle membrane periodically resets the pH clock that switches the system from acid to basic, resulting in self-sustained oscillations. We analyse the structure of the phase flow and of the limit cycle, which controls the dynamics for giant vesicles and dominates the pronouncedly stochastic oscillations in small vesicles of submicrometer size. To this end, we derive reduced models, which are amenable to analytic treatments that are complemented by numerical solutions, and obtain the period and amplitude of the oscillations as well as the parameter domain, where oscillatory behavior persists. We show that the accuracy of these predictions is highly sensitive to the employed reduction scheme. In particular, we suggest an accurate two-variable model and show its equivalence to a three-variable model that admits an interpretation in terms of a chemical reaction network. The faithful modeling of a single pH oscillator appears crucial for rationalizing experiments and understanding communication of vesicles and synchronization of rhythms.
description: submitted J. Phys. Chem. B
Sonnenfleckenzeichnung Nr. 272.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 25.11.1999, 08:30, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
LCAAJ audio for location 53193 (Żuromin, Poland)
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2021
Subjects: Yiddish language--Dialects
Yiddish language--Phonology
Language surveys
Ashkenazim--Social life and customs
Jews--Civilization

description: Żuromin, Poland (53.066078, 19.908905)
Lax comma categories of ordered sets
Creators: name: Clementino, Maria Manuel
name: Nunes, Fernando Lucatelli
Publisher: name: arXiv
Year: 2022
Subjects: subject: Category Theory (math.CT)
subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 06A07, 18A25, 18A30, 18N10, 18D20, 18E50

description: Let $\mathsf{Ord} $ be the category of (pre)ordered sets. Unlike $\mathsf{Ord}/X$, whose behaviour is well-known, not much can be found in the literature about the lax comma 2-category $\mathsf{Ord} //X$. In this paper we show that the forgetful functor $\mathsf{Ord} //X\to \mathsf{Ord} $ is topological if and only if $X$ is complete. Moreover, under suitable hypothesis, $\mathsf{Ord} // X$ is complete and cartesian closed if and only if $X$ is. We end by analysing descent in this category. Namely, when $X$ is complete and cartesian closed, we show that, for a morphism in $\mathsf{Ord} //X$, being pointwise effective for descent in $\mathsf{Ord} $ is sufficient, while being effective for descent in $\mathsf{Ord} $ is necessary, to be effective for descent in $\mathsf{Ord} //X$.
description: 12 pages
Sonnenfleckenzeichnung Nr. 4.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 06.01.1999, 09:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 1999

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 4.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Convolutional neural networks for valid and efficient causal inference
Creators: name: Ghasempour, Mohammad
name: Moosavi, Niloofar
name: de Luna, Xavier
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences
subject: 62G05, 62G20

description: Convolutional neural networks (CNN) have been successful in machine learning applications. Their success relies on their ability to consider space invariant local features. We consider the use of CNN to fit nuisance models in semiparametric estimation of the average causal effect of a treatment. In this setting, nuisance models are functions of pre-treatment covariates that need to be controlled for. In an application where we want to estimate the effect of early retirement on a health outcome, we propose to use CNN to control for time-structured covariates. Thus, CNN is used when fitting nuisance models explaining the treatment and the outcome. These fits are then combined into an augmented inverse probability weighting estimator yielding efficient and uniformly valid inference. Theoretically, we contribute by providing rates of convergence for CNN equipped with the rectified linear unit activation function and compare it to an existing result for feedforward neural networks. We also show when those rates guarantee uniformly valid inference. A Monte Carlo study is provided where the performance of the proposed estimator is evaluated and compared with other strategies. Finally, we give results on a study of the effect of early retirement on hospitalization using data covering the whole Swedish population.
description: 22 pages, 2 figure
Selective decay in fluids with advected quantities: MHD and Hall MHD
Creators: name: Gay-Balmaz, François
name: Holm, Darryl D.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Mathematical Physics (math-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Modifications of the equations of ideal fluid dynamics with advected quantities are introduced that allow selective decay of either the energy $h$ or the Casimir quantities $C$ in the Lie-Poisson formulation. The dissipated quantity (energy or Casimir, respectively) is shown to decrease in time until the modified system reaches an equilibrium state consistent with ideal energy-Casimir equilibria, namely $δ(h+C)=0$. The result holds for Lie-Poisson equations in general, independently of the Lie algebra and the choice of Casimir. This selective decay process is illustrated with a number of examples in 2D and 3D magnetohydrodynamics (MHD).
description: As published
LCAAJ audio for location 51112 (Apolda, Germany)
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2021
Subjects: Yiddish language--Dialects
Yiddish language--Phonology
Language surveys
Ashkenazim--Social life and customs
Jews--Civilization

description: Apolda, Germany (51.02601, 11.51555)
LCAAJ audio for location 52249 (Ruzhany, Belarus)
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2021
Subjects: Yiddish language--Dialects
Yiddish language--Phonology
Language surveys
Ashkenazim--Social life and customs
Jews--Civilization

description: Ruzhany, Belarus (52.86695, 24.892022)
$\mathcal{PT}$-symmetric effects in measurement-based quantum thermal machines
Creators: name: Santos, Jonas F. G.
name: Chattopadhyay, Pritam
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Measurement-based quantum thermal machines are fascinating models of thermodynamic cycles where measurement protocols play an important role in the performance and functioning of the cycle. Despite theoretical advances, interesting experimental implementations have been reported. Here we move a step further by considering in this class of cycle $\mathcal{PT}$-symmetric non-Hermitian Hamiltonians and their implications in quantum thermal machines fueled by generalized measurements. We present theoretical results indicating that $\mathcal{PT}$-symmetric effects and measurement protocols are related along the cycle. Furthermore, tuning the parameters suitably it is possible to improve the power output (engine configuration) and the cooling rate (refrigerator configuration), operating in the Otto limit, in a finite-time cycle that satisfies the quantum adiabatic theorem. Our model also allows switching the configuration of the cycle, engine, or refrigerator, depending on the strength of the measurement protocol.
title: How Metal Nuclearity Impacts Electrocatalytic H₂ Production in Thiocarbohydrazone-Based Complexes
Creators: name: Papadakis, Michael
name: Barrozo, Alexandre
name: Delmotte, Léa
name: Straistari, Tatiana
name: Shova, Sergiu
name: Réglier, Marius
name: Krewald, Vera
name: Bertaina, Sylvain
name: Hardré, Renaud
name: Orio, Maylis
Publisher: name: MDPI
Year: 2023

description: Thiocarbohydrazone-based catalysts feature ligands that are potentially electrochemically active. From the synthesis point of view, these ligands can be easily tailored, opening multiple strategies for optimization, such as using different substituent groups or metal substitution. In this work, we show the possibility of a new strategy, involving the nuclearity of the system, meaning the number of metal centers. We report the synthesis and characterization of a trinuclear nickel-thiocarbohydrazone complex displaying an improved turnover rate compared with its mononuclear counterpart. We use DFT calculations to show that the mechanism involved is metal-centered, unlike the metal-assisted ligand-centered mechanism found in the mononuclear complex. Finally, we show that two possible mechanisms can be assigned to this catalyst, both involving an initial double reduction of the system.
Adversarial Constrained Bidding via Minimax Regret Optimization with Causality-Aware Reinforcement Learning
Creators: name: Wang, Haozhe
name: Du, Chao
name: Fang, Panyan
name: He, Li
name: Wang, Liang
name: Zheng, Bo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Computer Science and Game Theory (cs.GT)
subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: The proliferation of the Internet has led to the emergence of online advertising, driven by the mechanics of online auctions. In these repeated auctions, software agents participate on behalf of aggregated advertisers to optimize for their long-term utility. To fulfill the diverse demands, bidding strategies are employed to optimize advertising objectives subject to different spending constraints. Existing approaches on constrained bidding typically rely on i.i.d. train and test conditions, which contradicts the adversarial nature of online ad markets where different parties possess potentially conflicting objectives. In this regard, we explore the problem of constrained bidding in adversarial bidding environments, which assumes no knowledge about the adversarial factors. Instead of relying on the i.i.d. assumption, our insight is to align the train distribution of environments with the potential test distribution meanwhile minimizing policy regret. Based on this insight, we propose a practical Minimax Regret Optimization (MiRO) approach that interleaves between a teacher finding adversarial environments for tutoring and a learner meta-learning its policy over the given distribution of environments. In addition, we pioneer to incorporate expert demonstrations for learning bidding strategies. Through a causality-aware policy design, we improve upon MiRO by distilling knowledge from the experts. Extensive experiments on both industrial data and synthetic data show that our method, MiRO with Causality-aware reinforcement Learning (MiROCL), outperforms prior methods by over 30%.
description: Accepted by SIGKDD2023
The Josephson junction as a quantum engine
Creators: name: Alicki, Robert
name: Horodecki, Michał
name: Jenkins, Alejandro
name: Łobejko, Marcin
name: Suárez, Gerardo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Superconductivity (cond-mat.supr-con)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We treat the Cooper pairs in the superconducting electrodes of a Josephson junction (JJ) as an open system, coupled via Andreev scattering to external baths of electrons. The disequilibrium between the baths generates the direct-current bias applied to the JJ. In the weak-coupling limit we obtain a Markovian master equation that provides a simple dynamical description consistent with the main features of the JJ, including the form of the current-voltage characteristic, its hysteresis, and the appearance under periodic voltage driving of discrete Shapiro steps. For small dissipation, our model also exhibits a self-oscillation of the JJ's electrical dipole with frequency $Ω= 2 e V / \hbar$ around mean voltage $V$. This self-oscillation, associated with "hidden attractors" of the nonlinear equations of motion, explains the observed production of monochromatic radiation with frequency $Ω$ and its harmonics. We argue that this picture of the JJ as a quantum engine resolves open questions about the Josephson effect as an irreversible process and could open new perspectives in quantum thermodynamics and in the theory of dynamical systems.
description: 27 pages, 9 figures. v2: references added. v3: more references added, several points clarified, discussion of superradiance dynamics in Sec. VI A improved and factor of 2 corrected. v4: typos fixed and other minor improvements. To appear in New Journal of Physics
Emergent axion response in multilayered metamaterials
Creators: name: Shaposhnikov, Leon
name: Mazanov, Maxim
name: Bobylev, Daniel A.
name: Wilczek, Frank
name: Gorlach, Maxim A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider the design of metamaterials whose behavior embodies the equations of axion electrodynamics. We derive an effective medium description of an assembly of magneto-optical layers with out-of-plane magnetization analytically and show how to achieve effective axion response with tunable parameters. We display some key predictions and validate them numerically.
description: 7 figures, 12 pages
Implementation and Performance Analysis of a Low Resolution OFDM System Prototype With Low Cost Hardware
Creators: name: de Souza, Eder O.
name: Dias, João T.
name: Gonçalves, Demerson N.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The present work focus on the implementation and analyze of performance of a low-resolution OFDM system prototype with low-cost hardware. A software defined radio (SDR) system was chosen in this implementation due to its various advantages over a traditional radio system. Among the options of SDR devices available, the use of universal software radio peripherals (USRP) was avoided due to its high cost, despite its popularity in this field of research. Alternatively, a combination of two low-cost SDRs, "Hackrf One" and "RTL- SDR Blog V3" with the GNU Radio, a popular, free and open source radio software, were used. Thus, it was possible to emulate the behavior of a low resolution ADC in the receiver, characterize its performance and estimate its energy savings. This allowed us to determine the feasibility of building a component with the analog-to-digital conversion function with few bits of resolution. We conclude that the performance of an ADC with at least 5 bits of resolution is pretty reasonable and that this reduction in the number of bits, in comparison to 8-bit ADC, represents a fairly expressive energy saving.
title: A Dynamic Recurrent Neural Network for Predicting Higher Heating Value of Biomass
Creators: name: Aghel, Babak
name: Yahya, Salah I.
name: Rezaei, Abbas
name: Alobaid, Falah
Publisher: name: MDPI
Year: 2023

description: The higher heating value (HHV) is the main property showing the energy amount of biomass samples. Several linear correlations based on either the proximate or the ultimate analysis have already been proposed for predicting biomass HHV. Since the HHV relationship with the proximate and ultimate analyses is not linear, nonlinear models might be a better alternative. Accordingly, this study employed the Elman recurrent neural network (ENN) to anticipate the HHV of different biomass samples from both the ultimate and proximate compositional analyses as the model inputs. The number of hidden neurons and the training algorithm were determined in such a way that the ENN model showed the highest prediction and generalization accuracy. The single hidden layer ENN with only four nodes, trained by the Levenberg–Marquardt algorithm, was identified as the most accurate model. The proposed ENN exhibited reliable prediction and generalization performance for estimating 532 experimental HHVs with a low mean absolute error of 0.67 and a mean square error of 0.96. In addition, the proposed ENN model provides a ground to clearly understand the dependency of the HHV on the fixed carbon, volatile matter, ash, carbon, hydrogen, nitrogen, oxygen, and sulfur content of biomass feedstocks.