cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Stability and Indecomposability of the Representations of Quivers of $A_n$-type
Creators: name: Huang, Pengfei
name: Hu, Zhi
Publisher: name: arXiv
Year: 2019
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: In his paper \cite{MR1}, Markus Reineke proposed a conjecture that there exists a stable weight system $Θ$ for every indecomposable representation of Dynkin type quiver. In this paper, we showed this conjecture is true for quivers of $A_n$-type by combinatorial construction of a special weight system. We also reinterpret this weight system in terms of semi-invariant theory.
description: 16 pages, with some minor revisions. To appear in Communications in Algebra
Creating with Ghosts: Identity and Artistic Purpose in Armenian Diaspora
Creators: Kouyoumdjian, Mary
Publisher: name: Columbia University
Year: 2021
Subjects: Musical composition
World history
Armenian massacres (1915-1923)
Civil War (Lebanon : 1975-1990)
Cultural property--Protection
Projection art
Multimedia (Art)
Armenians

description: The creative submission for my dissertation includes two of my documentary works: They Will Take My Island, a thirty-minute multimedia collaboration with filmmaker Atom Egoyan for amplified string octet, electronic track, and film, commissioned by the Metropolitan Museum of Art; and Paper Pianos, a ninety-minute staged collaboration with director Nigel Maister and projection artist Kevork Mourad. The written submission for my dissertation is an examination of the ways in which experiences around transgenerational trauma inform and manifest in my creative practice. I offer a summary of my own family history of survivors of the Armenian Genocide and Lebanese Civil War, as well as a survey of displacement amongst the Armenian community in the past century. Furthermore, I discuss identity processing as diaspora and the act of cultural preservation, as inspired by genocide survivor, composer, priest, writer, and musicologist, Komitas Vardapet. I later examine these ideas in the context of creating They Will Take My Island and Paper Pianos, both of which were constructively motivated by transgenerational survivor’s guilt and draw from extra-musical documentary and horror genre practices.
Gauge dependence in the theory of non-linear spacetime perturbations
Creators: name: Sonego, Sebastiano
name: Bruni, Marco
Publisher: name: arXiv
Year: 1997
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Diffeomorphism freedom induces a gauge dependence in the theory of spacetime perturbations. We derive a compact formula for gauge transformations of perturbations of arbitrary order. To this end, we develop the theory of Taylor expansions for one-parameter families (not necessarily groups) of diffeomorphisms. First, we introduce the notion of knight diffeomorphism, that generalises the usual concept of flow, and prove a Taylor's formula for the action of a knight on a general tensor field. Then, we show that any one-parameter family of diffeomorphisms can be approximated by a family of suitable knights. Since in perturbation theory the gauge freedom is given by a one-parameter family of diffeomorphisms, the expansion of knights is used to derive our transformation formula. The problem of gauge dependence is a purely kinematical one, therefore our treatment is valid not only in general relativity, but in any spacetime theory.
description: paper accepted for publication in Communications of Mathematical Physics; SISSA preprint 105/97/A. 10 pages and 2 figures, standard latex
Creating an Orderly Society: The Regulation of Marriage and Sex in the Dutch Atlantic World, 1621-1674
Creators: Hamer, Deborah
Publisher: name: Columbia University
Year: 2014
Subjects: Marriage
Sex customs
Marriage customs and rites
History
Europeans

description: Historians have long connected the emergence of the early modern state with increased efforts to discipline populations.  Allying with religious authorities to monitor private lives, states sought to limit sexual activity to marriage and to support patriarchal authority in order to create orderly societies and obedient subjects.  Governments legitimated their increased intrusions into people's lives by arguing that it was their responsibility to bring about moral reformation in their subjects, but their new interest was also rooted in achieving more direct control over individuals for the purposes of preventing crime and disorder, rationalizing tax collection, eliminating legal pluralities, and inculcating military discipline.
      This dissertation argues that the same motives that informed the policies of emerging states in this period lay at the heart of the Dutch West India Company's marriage regulation during its brief existence from 1621 to 1674.  Company representatives sought to institute and enforce strict marriage discipline upon their colonists, soldiers, sailors, conquered subjects, and indigenous allies in order to transform them into proper subjects and to extend Company governance over vast, new territories.  Like the centralizing states of the early modern period that justified their increased power by arguing that they were reforming their subjects, the West India Company responded to potential critics of their state-like power and their sovereign authority with the same rationale.
      Company efforts to regulate marriage and sex were, however, challenged by the existence of overlapping jurisdictions emerging both from the Dutch Republic's own tradition of legal plurality and from the existing institutions of conquered European populations and indigenous allies.  Whereas emerging absolutist states were able to either gain the cooperation of or eliminate institutions with competing claims to authority, examining the conflicts over marriage regulation in the Dutch colonies shows that the West India Company failed in its efforts to tame competing institutions and bring them under its authority.  Looking at the Company's governance through the lens of its marriage and sex regulation, therefore, upends traditional understandings of the Company as a trading enterprise and suggests that its directors were engaged in the process of state formation.  It also suggests a novel way to understand the Company's repeated setbacks and ultimate failure in 1674.  Despite its claims to absolute authority and its efforts to negotiate and secure this authority, competing institutions never acquiesced to Company jurisdiction.
Creating a Voice for Black Tech Entrepreneurs in Academic Literature
Creators: Chambers, Brittany Sachi
Publisher: name: Columbia University
Year: 2018
Subjects: Entrepreneurship
African Americans
Adult education
African American businesspeople

description: In a country where inventors and innovators are noted as being at liberty to enter and contribute to the free market space, conversely studies have found that Black tech entrepreneurs face greater difficulty launching and growing their businesses. A review of the literature suggests that many of these difficulties stem from the lingering effects of historical inequalities. These inequalities have existed for decades due to laws and regulations that once limited home ownership, income earning, credit access, inheritances, and educational opportunities. Additionally, literature in the tech arena has demonstrated a lack of diversity in the field. Pattern matching or preconceived standards have also been said to impact Black tech entrepreneurs’ opportunities to receive investments to launch and grow their businesses.
      While great dialogue has taken place in the tech arena around these disparities, little is known in academic literature about how Black tech entrepreneurs engage in the process of creating innovative brands and marketing their companies. In light of this, the researcher conducted a qualitative case study designed to explore black tech entrepreneurs’ perceptions of how they learn to launch and grow their businesses. This study engaged participants who self-identified as tech entrepreneurs of Black or African descent who have launched apps, websites, or hybrid companies in the United States.
      Among the key findings that emerged from the study were: An overwhelming majority of participants described that seeking the counsel of “expert” others was a key action in securing funding to grow their companies. Further, a strong majority of participants indicated that having a positive self-concept was a key facilitator in growing their businesses; while, an equal number indicated that a misalignment between the investor and entrepreneur inhibited their ability to grow.
      The tech entrepreneurial field can evolve through the increased trying on of differing perspectives by both investors and entrepreneurs; the continued development of diversity tech ecosystems and support networks; and, sustained progress in increasing the investment opportunities for Black tech entrepreneurs.
Additional file 2: of Validation of the short assessment of health literacy (SAHL-D) and short-form development: Rasch analysis
Creators: name: A. Woudstra
name: C. Meppelink
name: H. Pander Maat
name: J. Oosterhaven
name: M. Fransen
name: A. Dima
Publisher: name: figshare
Year: 2019
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Developmental Biology
subject: Science Policy
subject: Hematology

description: SAHL-D data. Item measures by study sample (Nâ =â 1231) in order of item difficulty. (DOCX 17 kb)
Additional file 3: of Validation of the short assessment of health literacy (SAHL-D) and short-form development: Rasch analysis
Creators: name: A. Woudstra
name: C. Meppelink
name: H. Pander Maat
name: J. Oosterhaven
name: M. Fransen
name: A. Dima
Publisher: name: figshare
Year: 2019
Subjects: subject: Medicine
subject: Molecular Biology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Developmental Biology

description: SAHL-D data. DIF per study sample (Nâ =â 1231). (DOCX 19 kb)
Requirements Baseline
Creators: name: Ciurean, Roxana L.
Publisher: name: Zenodo
Year: 2024

description: Deliverable D1.1 – Requirements Baseline provides the foundation for identifying, consolidating, and implementing the scientific requirements of the EO4MULTIHAZARDS project, under Work Package 100 (WP100). The deliverable was developed collaboratively by all project partners, with BGS leading and contributions from CMCC, EURAC, GMV, UT-ITC, UCL, and VU. WP100 focuses on consolidating the project’s scientific background, defining science cases and their objectives, project risk assessment, and delivering a comprehensive set of scientific and operational requirements.

This document represents an agreed, reviewed, and approved set of requirements that establish clear expectations for project outputs and outcomes. It serves as a baseline for tracking project progress and supports collaboration with a wide range of stakeholders, including scientific organizations, NGOs, public institutions, operational agencies, practitioners, and related project networks.
Additional file 16 of Dynamic genetic differentiation drives the widespread structural and functional convergent evolution of snake venom proteinaceous toxins
Creators: name: Xie, Bing
name: Dashevsky, Daniel
name: Rokyta, Darin
name: Ghezellou, Parviz
name: Fathinia, Behzad
name: Shi, Qiong
name: Richardson, Michael K.
name: Fry, Bryan G.
Publisher: name: figshare
Year: 2022
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 16. zoomable kunitz tree.pdf.
Poisson bracket, deformed bracket and gauge group actions in Kontsevich deformation quantization
Creators: name: Manchon, Dominique
Publisher: name: arXiv
Year: 2000
Subjects: subject: Quantum Algebra (math.QA)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 16S80; 53D17; 53D55; 58A50

description: We express the difference between Poisson bracket and deformed bracket for Kontsevich deformation quantization on any Poisson manifold by means of second derivative of the formality quasi-isomorphism. The counterpart on star products of the action of formal diffeomorphisms on Poisson formal bivector fields is also investigated.
description: 11 pages, one xypic figure. Minor changes on section IV
Homoclinic and heteroclinic intersections for lemon billiards
Creators: name: Jin, Xin
name: Zhang, Pengfei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37C83 37C29

description: We study the dynamical billiards on a symmetric lemon table $\mathcal{Q}(b)$, where $\mathcal{Q}(b)$ is the intersection of two unit disks with center distance $b$. We show that there exists $δ_0>0$ such that for all $b\in(1.5, 1.5+δ_0)$ (except possibly a discrete subset), the billiard map $F_b$ on the lemon table $\mathcal{Q}(b)$ admits crossing homoclinic and heteroclinic intersections. In particular, such lemon billiards have positive topological entropy.
description: Final version. To appear on the journal Advances in Mathematics
Time-changed fractional Ornstein-Uhlenbeck process
Creators: name: Ascione, Giacomo
name: Mishura, Yuliya
name: Pirozzi, Enrica
Publisher: name: arXiv
Year: 2019
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: We define a time-changed fractional Ornstein-Uhlenbeck process by composing a fractional Ornstein-Uhlenbeck process with the inverse of a subordinator. Properties of the moments of such process are investigated and the existence of the density is shown. We also provide a generalized Fokker-Planck equation for the density of the process.
description: 27 pages
Generalized Inversion of Nonlinear Operators
Creators: name: Gofer, Eyal
name: Gilboa, Guy
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistics Theory (math.ST)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Inversion of operators is a fundamental concept in data processing. Inversion of linear operators is well studied, supported by established theory. When an inverse either does not exist or is not unique, generalized inverses are used. Most notable is the Moore-Penrose inverse, widely used in physics, statistics, and various fields of engineering. This work investigates generalized inversion of nonlinear operators.
 We first address broadly the desired properties of generalized inverses, guided by the Moore-Penrose axioms. We define the notion for general sets, and then a refinement, termed pseudo-inverse, for normed spaces. We present conditions for existence and uniqueness of a pseudo-inverse and establish theoretical results investigating its properties, such as continuity, its value for operator compositions and projection operators, and others. Analytic expressions are given for the pseudo-inverse of some well-known, non-invertible, nonlinear operators, such as hard- or soft-thresholding and ReLU. We analyze a neural layer and discuss relations to wavelet thresholding.
 Next, the Drazin inverse, and a relaxation, are investigated for operators with equal domain and range. We present scenarios where inversion is expressible as a linear combination of forward applications of the operator. Such scenarios arise for classes of nonlinear operators with vanishing polynomials, similar to the minimal or characteristic polynomials for matrices. Inversion using forward applications may facilitate the development of new efficient algorithms for approximating generalized inversion of complex nonlinear operators.
description: A significant extension of the SSVM 2023 conference paper (see also v2 here), in particular, new sections 7--9
The Definition and Measurement of the Topological Entropy per Unit Volume in Parabolic PDE's
Creators: name: Collet, P.
name: Eckmann, J. -P.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Mathematical Physics (math-ph)
subject: Dynamical Systems (math.DS)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We define the topological entropy per unit volume in parabolic PDE's such as the complex Ginzburg-Landau equation, and show that it exists, and is bounded by the upper Hausdorff dimension times the maximal expansion rate. We then give a constructive implementation of a bound on the inertial range of such equations. Using this bound, we are able to propose a finite sampling algorithm which allows (in principle) to measure this entropy from experimental data.
description: 26 pages, 1 small figure
Additional file 1 of The frequency and clinical implication of mismatch repair protein deficiency in Chinese patients with ovarian clear cell carcinoma
Creators: name: Ye, Shuang
name: Zhou, Shuling
name: Zhong, Siyuan
name: Shan, Boer
name: Jiang, Wenhua
name: Yang, Wentao
name: Cai, Xu
name: Yang, Huijuan
Publisher: name: figshare
Year: 2022
Subjects: subject: Medicine
subject: Cell Biology
subject: Biotechnology
subject: Immunology
subject: FOS: Clinical medicine
subject: Mathematical Sciences not elsewhere classified
subject: Cancer
subject: Mental Health
subject: Computational Biology

description: Additional file 1: Supplementary Table 1. Clinical features of the study population (n = 108).
Monopis monachella
Creators: name: Huang, Guo-Hua
name: Chen, Liu-Sheng
name: Hirowatari, Toshiya
name: Nasu, Yoshitsugu
name: Wang, Ming
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Tineidae
Monopis
Monopis monachella

description: KEY TO SPECIES OF MONOPIS MONACHELLA SPECIES COMPLEX IN CHINA
 1. Brownish macula in white marking on upper side of forewing absent....................................... M. monachella
– Brownish macula in white marking on upper side of forewing present........................................................2
 2. Brownish macula included in white marking completely............................................................. M. longella
 – Brownish macula connected with outer black margin.....................................................  M. iunctio sp. nov.
description: Published as part of Huang, Guo-Hua, Chen, Liu-Sheng, Hirowatari, Toshiya, Nasu, Yoshitsugu & Wang, Ming, 2011, A revision of the Monopis monachella species complex (Lepidoptera: Tineidae) from China, pp. 1-14 in Zoological Journal of the Linnean Society 163 (1) on page 4, DOI: 10.1111/j.1096-3642.2011.00704.x, http://zenodo.org/record/10114758
Adaptively Enhancing Facial Expression Crucial Regions via Local Non-Local Joint Network
Creators: name: Shi, Guanghui
name: Mao, Shasha
name: Gou, Shuiping
name: Yan, Dandan
name: Jiao, Licheng
name: Xiong, Lin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Facial expression recognition (FER) is still one challenging research due to the small inter-class discrepancy in the facial expression data. In view of the significance of facial crucial regions for FER, many existing researches utilize the prior information from some annotated crucial points to improve the performance of FER. However, it is complicated and time-consuming to manually annotate facial crucial points, especially for vast wild expression images. Based on this, a local non-local joint network is proposed to adaptively light up the facial crucial regions in feature learning of FER in this paper. In the proposed method, two parts are constructed based on facial local and non-local information respectively, where an ensemble of multiple local networks are proposed to extract local features corresponding to multiple facial local regions and a non-local attention network is addressed to explore the significance of each local region. Especially, the attention weights obtained by the non-local network is fed into the local part to achieve the interactive feedback between the facial global and local information. Interestingly, the non-local weights corresponding to local regions are gradually updated and higher weights are given to more crucial regions. Moreover, U-Net is employed to extract the integrated features of deep semantic information and low hierarchical detail information of expression images. Finally, experimental results illustrate that the proposed method achieves more competitive performance compared with several state-of-the art methods on five benchmark datasets. Noticeably, the analyses of the non-local weights corresponding to local regions demonstrate that the proposed method can automatically enhance some crucial regions in the process of feature learning without any facial landmark information.
Fundamental Automorphisms of Clifford Algebras and an Extension of Dabrowski Pin Groups
Creators: name: Varlamov, Vadim V.
Publisher: name: arXiv
Year: 1999
Subjects: subject: Mathematical Physics (math-ph)
subject: Rings and Algebras (math.RA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Double coverings of the orthogonal groups of the real and complex spaces are considered. The relation between discrete transformations of these spaces and fundamental automorphisms of Clifford algebras is established, where an isomorphism between a finite group of the discrete transformations and an automorphism group of the Clifford algebras plays a central role. The complete classification of Dabrowski groups depending upon signatures of the spaces is given. Two types of Dabrowski quotient groups are introduced in case of odd-dimensional spaces. Application potentialities of the introduced quotient groups in Physics are discussed.
description: 30 pages, LaTeX2e, corrected version
Creative Small Businesses and Their Economic Impact on New York City's Neighborhoods
Creators: Lee, Hyun Seung
Publisher: name: Columbia University
Year: 2017
Subjects: City planning
Neighborhoods--Economic aspects
Community development, Urban
Economic development
Small business
Small business--Economic aspects

description: Richard Florida’s idea on “creative class” in the year 2002 led many researchers from diverse disciplines to seek the value of “creativity.” In his study, Florida argued that the creative class is a potential engine for metropolitan economic growth. This thesis is founded on this earlier concept and investigates the extent to which the growth of creative small businesses can impact the economic conditions of neighborhoods in New York City. Rather than assessing the issue from a metropolitan scale, however, this study zooms in and focuses on the neighborhood level in order to detect impacts at a micro-level. Through the mapping of creative small businesses (CSB) in New York City neighborhoods over time, this study found that there was a strong growth of creative small businesses in Brooklyn from 2000 to 2012. Decreases in unemployment rates and increases in median rent values were evaluated through mapping and statistical analyses to find that CSB might affect the decline of unemployment rates at the neighborhood boundary level. Also, median rent changes studied at the borough level showed an inverse relationship between creative small business growth and increase in rent values in Brooklyn, while the opposite was found for the Bronx and Queens. Since original property characteristics and rent values are much distinct in each borough and yield divergent results from the analysis, this thesis found that it is important to understand the relationship between CSB growth and rent values at the boroughs separately.
From Qubits to Continuous-Variable Quantum Computation
Creators: name: Sanders, Barry C
name: Bartlett, Stephen D.
name: de Guise, Hubert
Publisher: name: arXiv
Year: 2002
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: By encoding a qudit in a harmonic oscillator and investigating the d --> infinity limit, we give an entirely new realization of continuous-variable quantum computation. The generalized Pauli group is generated by number and phase operators for harmonic oscillators.
description: 7 pages, presented at ICSSUR'01 (Boston, MA, USA, June 2001)
Poincaré Symmetry from Heisenberg's Uncertainty Relations
Creators: name: Baskal, Sibel
name: Kim, Young S.
name: Noz, Marilyn E.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: It is noted that the single-variable Heisenberg commutation relation contains the symmetry of the $Sp(2)$ group which is isomorphic to the Lorentz group applicable to one time-like dimension and two space-like dimensions, known as the $O(2,1)$ group. According to Paul A. M. Dirac, from the uncertainty commutation relations for two variables, it possible to construct the de Sitter group $O(3,2)$, namely the Lorentz group applicable to three space-like variables and two time-like variables. By contracting one of the time-like variables in $O(3,2)$, it is possible, to construct the inhomogeneous Lorentz group $IO(3,1)$ which serves as the fundamental symmetry group for quantum mechanics and quantum field theory in the Lorentz covariant world. This $IO(3,1)$ group is commonly known as the Poincaré group.
description: 10 pages, 1 figure
Additional file 1: of Validation of the short assessment of health literacy (SAHL-D) and short-form development: Rasch analysis
Creators: name: A. Woudstra
name: C. Meppelink
name: H. Pander Maat
name: J. Oosterhaven
name: M. Fransen
name: A. Dima
Publisher: name: figshare
Year: 2019
Subjects: subject: Medicine
subject: Pharmacology
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Developmental Biology
subject: Marine Biology
subject: Hematology

description: SAHL-D data. Item measures by demographic groups (Nâ =â 1231) in order of difficulty. (DOCX 20 kb)
Hyper-entangling mesoscopic bound states
Creators: name: Sreedharan, Aparna
name: Kuriyattil, Sridevi
name: Wüster, Sebastian
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We predict hyper-entanglement generation during binary scattering of mesoscopic bound states, solitary waves in Bose-Einstein condensates containing thousands of identical Bosons. The underlying many-body Hamiltonian must not be integrable, and the pre-collision quantum state of the solitons fragmented. Under these conditions, we show with pure state quantum field simulations that the post-collision state will be hyper-entangled in spatial degrees of freedom and atom number within solitons, for realistic parameters. The effect links aspects of non-linear systems and quantum-coherence and the entangled post-collision state challenges present entanglement criteria for identical particles. Our results are based on simulations of colliding quantum solitons in a quintic interaction model beyond the mean-field, using the truncated Wigner approximation.
description: 6 figures
Mirror Symmetry of Calabi-Yau Manifolds and Flat Coordinates
Creators: name: Noguchi, Masayuki
Publisher: name: arXiv
Year: 1996
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Algebraic Geometry (math.AG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study mirror symmetry of Calabi-Yau manifolds within the framework of the Gauss-Manin system. Applying the flat coordinates to the Gauss-Manin system for the periods, we derive differential equations for the mirror map in addition to the ordinary Picard-Fuchs equations for the periods. These equations are obtained for a class of one-parameter models and a two-parameter model of Fermat type Calabi-Yau manifolds.
description: 27 pages, LaTeX, no figures
On a category of extensions whose endomorphism rings have at most four maximal ideals
Creators: name: Campanini, Federico
name: Facchini, Alberto
Publisher: name: arXiv
Year: 2025
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics

description: We describe the endomorphism ring of a short exact sequences $0 \to A_R \to B_R \to C_R \to 0$ with $A_R$ and $C_R$ uniserial modules and the behavior of these short exact sequences as far as their direct sums are concerned.
Additional file 7: of The effects of meteoric diagenesis on the geochemical composition and microstructure of Pliocene fossil Terebratalia coreanica and Laqueus rubellus brachiopod shells from northeastern Japan
Creators: name: Fujioka, Hiroshi
name: Takayanagi, Hideko
name: Yamamoto, Koshi
name: Iryu, Yasufumi
Publisher: name: figshare
Year: 2019
Subjects: subject: Molecular Biology
subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Science Policy

description: Doc. S1. Estimation of Î´13C and Î´18O values of equilibrium calcite. (DOCX 25 kb)
Non-Smooth Integrability Theory
Creators: name: Hosoya, Yuhki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Theoretical Economics (econ.TH)
subject: FOS: Economics and business
subject: 91B16

description: We study a method for calculating the utility function from a candidate of a demand function that is not differentiable, but is locally Lipschitz. Using this method, we obtain two new necessary and sufficient conditions for a candidate of a demand function to be a demand function. The first concerns the Slutsky matrix, and the second is the existence of a concave solution to a partial differential equation. Moreover, we show that the upper semi-continuous weak order that corresponds to the demand function is unique, and that this weak order is represented by our calculated utility function. We provide applications of these results to econometric theory. First, we show that, under several requirements, if a sequence of demand functions converges to some function with respect to the metric of compact convergence, then the limit is also a demand function. Second, the space of demand functions that have uniform Lipschitz constants on any compact set is compact under the above metric. Third, the mapping from a demand function to the calculated utility function becomes continuous. We also show a similar result on the topology of pointwise convergence.
Complete positivity of nonlinear evolution: A case study
Creators: name: Czachor, Marek
name: Kuna, Maciej
Publisher: name: arXiv
Year: 1997
Subjects: subject: Quantum Physics (quant-ph)
subject: Chaotic Dynamics (nlin.CD)
subject: Functional Analysis (math.FA)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Simple Hartree-type equations lead to dynamics of a subsystem that is not completely positive in the sense accepted in mathematical literature. In the linear case this would imply that negative probabilities have to appear for some system that contains the subsystem in question. In the nonlinear case this does not happen because the mathematical definition is physically unfitting as shown on a concrete example.
description: extended version, 3 appendices added (on mixed states, projection postulate, nonlocality), to be published in Phys. Rev. A
On Measures and Measurements: a Fibre Bundle approach to Contextuality
Creators: name: Cunha, Marcelo Terra
Publisher: name: arXiv
Year: 2019
Subjects: subject: Probability (math.PR)
subject: Algebraic Topology (math.AT)
subject: Quantum Physics (quant-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 28E05

description: Contextuality is the failure of "local" probabilistic models to become global ones. In this paper we introduce the notions of \emph{measurable fibre bundles}, \emph{probability fibre bundles}, and \emph{sample fibre bundle} which capture and make precise the former statement. The central notions of contextuality are discussed under this formalism, examples worked out, and some new aspects pointed out.
description: 14 pages; no figures; Purdue-Winer Memorial Lectures 2018; submitted to Phil. Trans. Roy. Soc. A. Comments are very welcome
Distinguishing N-acetylneuraminic acid linkage isomers on glycopeptides by ion mobility-mass spectrometry
Creators: name: Hinneburg, H.
name: Hofmann, J.
name: Struwe, W. B.
name: Thader, A.
name: Altmann, F.
name: Varón Silva, D.
name: Seeberger, P. H.
name: Pagel, K.
name: Kolarich, D.
Publisher: name: Freie Universität Berlin
Year: 2016
Subjects: subject: 500 Naturwissenschaften und Mathematik::540 Chemie

description: Differentiating the structure of isobaric glycopeptides represents a major challenge for mass spectrometry-based characterisation techniques. Here we show that the regiochemistry of the most common N-acetylneuraminic acid linkages of N-glycans can be identified in a site-specific manner from individual glycopeptides using ion mobility-mass spectrometry analysis of diagnostic fragment ions.
Current densities in density-functional theory
Creators: name: Lieb, Elliott H.
name: Schrader, Robert
Publisher: name: Freie Universität Berlin
Year: 2013
Subjects: subject: 500 Naturwissenschaften und Mathematik::530 Physik

description: It is well known that any given density ρ(x) can be realized by a determinantal wave function for N particles. The question addressed here is whether any given density ρ(x) and current density j(x) can be simultaneously realized by a (finite kinetic energy) determinantal wave function. In case the velocity field v(x)=j(x)/ρ(x) is curlfree, we provide a solution for all N, and we provide an explicit upper bound for the energy. If the velocity field is not curl-free, there is a finite energy solution for all N≥4, but we do not provide an explicit energy bound in this case. For N=2 we provide an example of a non-curl-free velocity field for which there is a solution and an example for which there is no solution. The case N=3 with a non-curl-free velocity field is left open.
Visual-based Safe Landing for UAVs in Populated Areas: Real-time Validation in Virtual Environments
Creators: name: Tovanche-Picon, Hector
name: Gonzalez-Trejo, Javier
name: Flores-Abad, Angel
name: Mercado-Ravell, Diego
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Safe autonomous landing for Unmanned Aerial Vehicles (UAVs) in populated areas is a crucial aspect for successful urban deployment, particularly in emergency landing situations. Nonetheless, validating autonomous landing in real scenarios is a challenging task involving a high risk of injuring people. In this work, we propose a framework for real-time safe and thorough evaluation of vision-based autonomous landing in populated scenarios, using photo-realistic virtual environments. We propose to use the Unreal graphics engine coupled with the AirSim plugin for drone's simulation, and evaluate autonomous landing strategies based on visual detection of Safe Landing Zones (SLZ) in populated scenarios. Then, we study two different criteria for selecting the "best" SLZ, and evaluate them during autonomous landing of a virtual drone in different scenarios and conditions, under different distributions of people in urban scenes, including moving people. We evaluate different metrics to quantify the performance of the landing strategies, establishing a baseline for comparison with future works in this challenging task, and analyze them through an important number of randomized iterations. The study suggests that the use of the autonomous landing algorithms considerably helps to prevent accidents involving humans, which may allow to unleash the full potential of drones in urban environments near to people.
Emergence of a bicritical end point in the random crystal field Blume-Capel model
Creators: name: Sumedha
name: Mukherjee, Soheli
Publisher: name: arXiv
Year: 2019
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We obtain the phase diagram for the Blume-Capel model with bimodal distribution for random crystal fields, in the space of three fields: temperature, crystal field and magnetic field. We find that three critical lines meet at a tricritical point, but only for weak disorder. As disorder strength increases there is no tricritical point in the phase diagram. We instead find a bicritical end point, where only two of the critical lines meet on a first order surface in the H=0 plane. For intermediate strengths of disorder, the phase diagram has critical end points along with the bicritical end point. One needs to look at the phase diagram in the space of three fields to identify various such multicritical points.
description: Replaced with the published version
Abelian BF Theories and Knot Invariants
Creators: name: Cattaneo, Alberto S.
Publisher: name: arXiv
Year: 1996
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In the context of the Batalin-Vilkovisky formalism, a new observable for the Abelian BF theory is proposed whose vacuum expectation value is related to the Alexander-Conway polynomial. The three-dimensional case is analyzed explicitly, and it is proved to be anomaly free. Moreover, at the second order in perturbation theory, a new formula for the second coefficient of the Alexander-Conway polynomial is obtained. An account on the higher-dimensional generalizations is also given.
description: 50 pages, LaTeX file; a few minor corrections added
Halo Spin from Primordial Inner Motions
Creators: name: Neyrinck, Mark C.
name: Aragon-Calvo, Miguel A.
name: Falck, Bridget
name: Szalay, Alexander S.
name: Wang, Jie
Publisher: name: arXiv
Year: 2019
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The standard explanation for galaxy spin starts with the tidal-torque theory (TTT), in which an ellipsoidal dark-matter protohalo, which comes to host the galaxy, is torqued up by the tidal gravitational field around it. We discuss a complementary picture, using the relatively familiar velocity field, instead of the tidal field, whose intuitive connection to the surrounding, possibly faraway matter arrangement is more obscure. In this 'spin from primordial inner motions' (SPIM) concept, implicit in TTT derivations but not previously emphasized, the angular momentum from the gravity-sourced velocity field inside a protohalo largely cancels out, but has some excess from the aspherical outskirts. At first, the net spin scales according to linear theory, a sort of comoving conservation of familiar angular momentum. Then, at collapse, it is conserved in physical coordinates. Small haloes are then typically subject to secondary exchanges of angular momentum. The TTT is useful for analytic estimates. But a literal interpretation of the TTT is inaccurate in detail, without some implicit concepts about smoothing of the velocity and tidal fields. This could lead to misconceptions, for those first learning about how galaxies come to spin. Protohaloes are not perfectly ellipsoidal and do not uniformly torque up, as in a naive interpretation of the TTT; their inner velocity fields retain substantial dispersion. Furthermore, quantitatively, given initial conditions and protohalo boundaries, SPIM is more direct and accurate than the TTT to predict halo spins. We also discuss how SPIM applies to rotating filaments, and the relation between halo mass and spin, in which the total spin of a halo can be thought of as a sum of random contributions.
description: Accepted to OJA (Open Journal of Astrophysics). 3 movies at https://www.youtube.com/playlist?list=PLJxZSP5_6rBmo7Rz8JgnE1eI2bxRGXGCT
Creditor coordination effects and bankruptcy prediction
Creators: Lee, Hyun Ah
Publisher: name: Columbia University
Year: 2011
Subjects: Accounting

description: This study investigates the increase in forecasting accuracy of hazard rate bankruptcy prediction models with creditor coordination effects over the forecasting period 1990-2009. A firm's probability of bankruptcy is likely to be marginally affected by creditors' coordination behavior, since failure to coordinate may result in premature foreclosure, denial of refinancing, or disagreement over private restructuring. Applying findings from prior literature, I present creditor coordination effects as interactions between the ex ante likelihood of creditor coordination failure and a firm's information characteristics. The most striking finding of this study is an increase, on average, of 10% in the out-of-sample forecasting accuracy of private firm prediction models with creditor coordination effects. The contributions of this study are twofold, (1) the hazard rate model results provide evidence that creditor coordination can exert marginal effects on firms' probability of bankruptcy, and (2) the forecast accuracy results suggest that incorporating creditor coordination effects can significantly improve the forecasting accuracy of bankruptcy prediction models for private firms.
Harmonic oscillator well with a screened Coulombic core is quasi-exactly solvable
Creators: name: Znojil, Miloslav
Publisher: name: arXiv
Year: 1999
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 81Q05

description: In the quantization scheme which weakens the hermiticity of a Hamiltonian to its mere PT invariance the superposition V(x) = x^2+ Ze^2/x of the harmonic and Coulomb potentials is defined at the purely imaginary effective charges (Ze^2=if) and regularized by a purely imaginary shift of x. This model is quasi-exactly solvable: We show that at each excited, (N+1)-st harmonic-oscillator energy E=2N+3 there exists not only the well known harmonic oscillator bound state (at the vanishing charge f=0) but also a normalizable (N+1)-plet of the further elementary Sturmian eigenstates ψ_n(x) at eigencharges f=f_n > 0, n = 0, 1, ..., N. Beyond the first few smallest multiplicities N we recommend their perturbative construction.
description: 13 pages, Latex file, to appear in J. Phys. A: Math. Gen
Surfaces of Albanese general type and the Severi Conjecture
Creators: name: Manetti, Marco
Publisher: name: arXiv
Year: 2000
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14J29

description: In 1932 F. Severi claimed, with an incorrect proof, that every smooth minimal projective surface $S$ such that the bundle $Ω^1_S$ is generically generated by global sections satisfies the topological inequality $2c_1^2(S)\ge c_2(S)$. According to Enriques-Kodaira classification, the above inequality is easily verified when the Kodaira dimension of the surface is $\le 1$, while for surfaces of general type it is still an open problem known as Severi conjecture. In this paper we prove Severi conjecture under the additional mild hypothesis that $S$ has ample canonical bundle. Moreover, under the same assumption, we prove that $2c_1^2(S)=c_2(S)$ if and only if $S$ is a double cover of an abelian surface.
description: Revised version, with simplified proofs, of an earlier preprint (1997). Latex: 22 pages
Credit Risk Modeling and Analysis Using Copula Method and Changepoint Approach to Survival Data
Creators: Qian, Bo
Publisher: name: Columbia University
Year: 2013
Subjects: subject: Statistics
subject: FOS: Mathematics

description: This thesis consists of two parts. The first part uses Gaussian Copula and Student's t Copula as the main tools to model the credit risk in securitizations and re-securitizations. The second part proposes a statistical procedure to identify changepoints in Cox model of survival data. The recent 2007-2009 financial crisis has been regarded as the worst financial crisis since the Great Depression by leading economists. The securitization sector took a lot of blame for the crisis because of the connection of the securitized products created from mortgages to the collapse of the housing market. The first part of this thesis explores the relationship between securitized mortgage products and the 2007-2009 financial crisis using the Copula method as the main tool. We show in this part how loss distributions of securitizations and re-securitizations can be derived or calculated in a new model. Simulations are conducted to examine the effectiveness of the model. As an application, the model is also used to examine whether and where the ratings of securitized products could be flawed. On the other hand, the lag effect and saturation effect problems are common and important problems in survival data analysis. They belong to a general class of problems where the treatment effect takes occasional jumps instead of staying constant throughout time. Therefore, they are essentially the changepoint problems in statistics. The second part of this thesis focuses on extending Lai and Xing's recent work in changepoint modeling, which was developed under a time series and Bayesian setup, to the lag effect problems in survival data. A general changepoint approach for Cox model is developed. Simulations and real data analyses are conducted to illustrate the effectiveness of the procedure and how it should be implemented and interpreted.
Detection of Small Holes by the Scale-Invariant Robust Density-Aware Distance (RDAD) Filtration
Creators: name: Siu, Chunyin
name: Samorodnitsky, Gennady
name: Yu, Christina Lee
name: Yao, Andrey
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistics Theory (math.ST)
subject: Computational Geometry (cs.CG)
subject: Algebraic Topology (math.AT)
subject: Machine Learning (stat.ML)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 62R40, 55N31, 52R40, 68T09

description: A novel topological-data-analytical (TDA) method is proposed to distinguish, from noise, small holes surrounded by high-density regions of a probability density function. The proposed method is robust against additive noise and outliers. Traditional TDA tools, like those based on the distance filtration, often struggle to distinguish small features from noise, because both have short persistences. An alternative filtration, called the Robust Density-Aware Distance (RDAD) filtration, is proposed to prolong the persistences of small holes of high-density regions. This is achieved by weighting the distance function by the density in the sense of Bell et al. The concept of distance-to-measure is incorporated to enhance stability and mitigate noise. The persistence-prolonging property and robustness of the proposed filtration are rigorously established, and numerical experiments are presented to demonstrate the proposed filtration's utility in identifying small holes.
description: 39 pages, 38 figs, J Appl. and Comput. Topology (2024). GitHub: [github.com/c-siu/RDAD]. Published version: [rdcu.be/dCXLa]. Diff of v2/3: added publication info, NO post-submission improvements (Cor2-3 rephrased and proven, setup of Sec4.1 explained, complexity computed in Sec6.1, Thm5 simplified, comparison with DTM in Sec1,8, streamlining), so no change in pdf. Diff of v1/2: more thms, more discussion on conformality, fewer egs