cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Entwicklung einer netzfreien Simulationsmethode auf Basis der flexiblen Elemente
Creators: name: Bode, Tobias
Publisher: name: Hannover : Gottfried Wilhelm Leibniz Universität
Year: 2017
Subjects: subject: Finite Element Methode
subject: OTM Methode
subject: flexible Finite Element Methode
subject: Finite-Elemente-Methode
subject: FEM
subject: Numerisches Verfahren
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau

description: Die Finite Element Methode (FEM) hat sich im Ingenieurwesen aufgrund seiner stabilen und numerisch genauen Approximation der Lösung von partiellen Differenzialgleichungen als Simulationswerkzeug bewährt. Aufgrund der Unterteilung des Lösungsgebiets in feste Elemente sind bei sehr großen Deformationen zusätzliche Algorithmen von Nöten, die meist die Stabilität und Genauigkeit negativ beeinflussen. Netzfreie Simulationsverfahren, wie die ”Optimal Transportation Meshfree“ (OTM) Methode, bestechen gerade hierbei durch Flexibilität, da keine feste Konnektivität zwischen einzelnen Knoten benötigt wird. Anstatt fester Elemente wird die Anzahl von Knoten, die den jeweiligen Materialpunkt beeinflusst, in jedem Zeitpunkt durch einen Suchalgorithmus neu bestimmt. Dieser Bereich wird dabei als Einflussgebiet des Materialpunkts bezeichnet. Auf der anderen Seite sind netzfreie Verfahren von Haus aus nicht stabil. Einer der Hauptgründe ist die Unterintegration in den Einflussgebieten der Materialpunkte. Daher soll im Rahmen dieser Studienarbeit die OTM Methode dahingehend erweitert werden, dass zusätzliche Integrationspunkte in das Einflussgebiet des jeweiligen Materialpunkts gelegt wird. Besonderer Fokus soll dabei auf die benötigte Anzahl von Integrationspunkten und die Kopplung zu ”Mean Value“ Ansatzfunktionen gelegt werden. Aufgrund der dadurch entstehenden Nähe zum Ablaufschema der FEM, soll dieses Verfahren als flexible Finite Element Methode bezeichnet werden. Nach der Implementation des neuen Algorithmus soll des Weiteren der Vorteil der neuen Methode anhand von Beispielen untersucht werden.
Quantum curves and conformal field theory
Creators: name: Manabe, Masahide
name: Sułkowski, Piotr
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: To a given algebraic curve we assign an infinite family of quantum curves (Schrödinger equations), which are in one-to-one correspondence with, and have the structure of, Virasoro singular vectors. For a spectral curve of a matrix model we build such quantum curves out of an appropriate representation of the Virasoro algebra, encoded in the structure of the $α/β$-deformed matrix integral and its loop equation. We generalize this construction to a large class of algebraic curves by means of a refined topological recursion. We also specialize this construction to various specific matrix models with polynomial and logarithmic potentials, and among other results, show that various ingredients familiar in the study of conformal field theory (Ward identities, correlation functions and a representation of Virasoro operators acting thereon, BPZ equations) arise upon specialization of our formalism to the multi-Penner matrix model.
description: 90 pages, published version
Stochastic population growth in spatially heterogeneous environments: The density-dependent case
Creators: name: Hening, Alexandru
name: Nguyen, Dang H.
name: Yin, George
Publisher: name: arXiv
Year: 2016
Subjects: subject: Probability (math.PR)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Mathematics
subject: FOS: Biological sciences
subject: 92D25, 37H15, 60H10

description: This work is devoted to studying the dynamics of a structured population that is subject to the combined effects of environmental stochasticity, competition for resources, spatio-temporal heterogeneity and dispersal. The population is spread throughout $n$ patches whose population abundances are modelled as the solutions of a system of nonlinear stochastic differential equations living on $[0,\infty)^n$. We prove that $r$, the stochastic growth rate of the total population in the absence of competition, determines the long-term behaviour of the population. The parameter $r$ can be expressed as the Lyapunov exponent of an associated linearized system of stochastic differential equations. Detailed analysis shows that if $r>0$, the population abundances converge polynomially fast to a unique invariant probability measure on $(0,\infty)^n$, while when $r<0$, the population abundances of the patches converge almost surely to $0$ exponentially fast. This generalizes and extends the results of Evans et al (2014 J. Math. Biol.) and proves one of their conjectures. Compared to recent developments, our model incorporates very general density-dependent growth rates and competition terms. Furthermore, we prove that persistence is robust to small, possibly density dependent, perturbations of the growth rates, dispersal matrix and covariance matrix of the environmental noise. Our work allows the environmental noise driving our system to be degenerate. This is relevant from a biological point of view since, for example, the environments of the different patches can be perfectly correlated. As an example we fully analyze the two-patch case, $n=2$, and show that the stochastic growth rate is a decreasing function of the dispersion rate. In particular, coupling two sink patches can never yield persistence, in contrast to the results from the non-degenerate setting treated by Evans et al.
description: 43 pages, 1 figure, edited according to the suggestion of the referees, to appear in Journal of Mathematical Biology
Using the Automata Processor for Fast Pattern Recognition in High Energy Physics Experiments - A Proof of Concept
Creators: name: Wang, Michael H. L. S.
name: Cancelo, Gustavo
name: Green, Christopher
name: Guo, Deyuan
name: Wang, Ke
name: Zmuda, Ted
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We explore the Micron Automata Processor (AP) as a suitable commodity technology that can address the growing computational needs of pattern recognition in High Energy Physics (HEP) experiments. A toy detector model is developed for which an electron track confirmation trigger based on the Micron AP serves as a test case. Although primarily meant for high speed text-based searches, we demonstrate a proof of concept for the use of the Micron AP in a HEP trigger application.
Origin of long-lived coherence and excitation dynamics in pigment-protein complexes
Creators: name: Zhang, Zhedong
name: Wang, Jin
Publisher: name: arXiv
Year: 2015
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We explore the mechanism for the long-lived quantum coherence by considering the discrete phonon modes: these vibrational modes effectively weaken the exciton-environment interaction, due to the new composite (polaron) formed by excitons and vibrons. This subsequently demonstrates the role of vibrational coherence which greatly contributes to long-lived feature of the excitonic coherence that has been observed in femtosecond experiments. The estimation of the timescale of coherence elongated by vibrational modes is given in an analytical manner. To test the validity of our theory, we study the pigment-protein complex in detail by exploring the energy transfer and coherence dynamics. The ground-state vibrational coherence generated by incoherent radiations is shown to be long-survived and is demonstrated to be significant in promoting the excitation energy transfer. This is attributed to the nonequilibriumness of the system caused by the detailed-balance-breaking, which funnels the downhill migration of excitons.
description: 9 pages, 4 figures
Advanced nanostructures for thermal management and heat regulation
Creators: name: Jing, Lin
Publisher: name: Carnegie Mellon University
Year: 2023
Subjects: classificationCode: 91299
subject: Materials Engineering not elsewhere classified

description: The pursuit of high electronics performance in a variety of applications has led to a dramatic increase in processor power density, and this trend is expected to continue. Despite the recent advancements in thermal management technologies, the stringent environment poses new challenges to heat regulation. For heat rejection, interfaces between materials have become crucial barriers to thermal transport. Therefore, it is imperative to develop high-performance thermal interface materials (TIM) that can thermally bridge the interface to meet the more severe needs. In terms of thermal infrared emission, the capability of artificially overcoming its intrinsic incoherence and realizing its manipulation in a controllable manner is also in demand. In this dissertation, we developed a nanostructured 3D “sandwich” TIM composed of graphene-coated copper nanowires (g-CuNWs) sandwiched between two thin copper films. From the thermal (frequency domain thermoreflectance) and mechanical (nanoindentation) characterizations, this “sandwich” TIM reveals ultralow thermal resistance which is 1 order of magnitude lower than solder, while at the same time, ultrahigh mechanical compliance and high flexibility. In order to eliminate the reliance on the soldering process, a double-sided CuNWs-in-glue composite film is achieved. The long-term reliability of both the 3D “sandwich” and the composite film is demonstrated by the temperature cycling test. As for thermal infrared emission, to enable radiative heat flux manipulation in a controllable manner, a near-field thermal rectifier is first studied. It is based on nanowire and nanocross pairs while one terminal being phase change material, vanadium dioxide (VO2). Consequently, a tunable bidirectional thermal rectification effect is manifested. Finally, an electrically-driven metastructure based on Yagi-Uda nanoantenna is designed and analyzed for artificially surmounting the incoherence of thermal emission.
Full characterization of a spin liquid phase: from topological entropy to robustness and braid statistics
Creators: name: Jahromi, Saeed S.
name: Langari, Abdollah
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We use the topological entanglement entropy (TEE) as an efficient tool to fully characterize the Abelian phase of a $\mathbb{Z}_2 \times \mathbb{Z}_2$ spin liquid emerging as the ground state of topological color code (TCC), which is a class of stabilizer states on the honeycomb lattice. We provide the fusion rules of the quasiparticle (QP) excitations of the model by introducing single- or two-body operators on physical spins for each fusion process which justify the corresponding fusion outcome. Beside, we extract the TEE from Renyi entanglement entropy (EE) of the TCC, analytically and numerically by finite size exact diagonalization on the disk shape regions with contractible boundaries. We obtain that the EE has a local contribution, which scales linearly with the boundary length in addition to a topological term, i.e. the TEE, arising from the condensation of closed strings in the ground state. We further investigate the ground state dependence of the TEE on regions with non-contractible boundaries, i.e. by cutting the torus to half cylinders, from which we further identify multiple independent minimum entropy states (MES) of the TCC and then extract the U and S modular matrices of the system, which contain the self and mutual statistics of the anyonic QPs and fully characterize the topological phase of the TCC. Eventually, we show that, in spite of the lack of a local order parameter, TEE and other physical quantities obtained from ground state wave function such as entanglement spectrum (ES) and ground state fidelity are sensitive probes to study the robustness of a topological phase. We find that the topological order in the presence of a magnetic field persists until the vicinity of the transition point, where the TEE and fidelity drops to zero and the ES splits severely, signaling breakdown of the topological phase of the TCC.
2019 International Aircraft Cabin Air Conference : Conference Proceedings – Presentations
Creators: name: Global Cabin Air Quality Executive (GCAQE)
Publisher: name: Hamburg : Aircraft Design and Systems Group (AERO), Department of Automotive and Aeronautical Engineering, Hamburg University of Applied Sciences
Year: 2019
Subjects: subject: aircraft
subject: cabin
subject: cabin air
subject: ECS
subject: tricresyl phosphate
subject: TCP
subject: air
subject: contamination
subject: Konferenzschrift
subject: Luftfahrt
subject: Luftfahrzeug
subject: Passagierflugzeug
subject: Flugzeugkabine
subject: Trikresylphosphat
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau::629,1 | Luft- und Raumfahrttechnik
subject: Aeronautics
subject: Airplanes
subject: Air--Pollution
subject: Aircraft Cabins

description: The International Aircraft Cabin Air Conferences are developing into a series of conferences organized every two years. The conferences are mapping the business, regulatory and technical solutions to aircraft cabin air contamination. The conferences in 2017 and 2019 provided networking opportunities for those seeking to understand the subject of contaminated air, the flight safety implications, the latest scientific and medical evidence investigating the contaminated air debate and the solutions available to airlines and aircraft operators. The two conferences held so far have been the most in-depth conferences ever on the topic of aircraft cabin air contamination. In total 30 presentations were given at the 2019 International Aircraft Cabin Air Conference (ACA 2019). This document contains the 25 presentations provided by the authors. It combines the presentations into one PDF for further dissemination and archiving.
Grokya: a Privacy-Friendly Framework for Ubiquitous Computing
Creators: name: Farinha, Daniel Filipe G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computers and Society (cs.CY)
subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: In a world where for-profit enterprises are increasingly looking to maximize profits by engaging in privacy invading consumer-profiling techniques, the rise of ubiquitous computing and the Internet of Things (IoT) poses a major problem. If not acted upon quickly, the combination of Big Data with IoT will explode into a dystopian world that even George Orwell could not have predicted. The proposed project aims to fill a gap that no other solution is addressing, which is to reach a win-win scenario that works for both the enterprises and the consumers. It aims to do this by creating the building blocks for a consumer owned infrastructure that can provide both privacy for the user, and still enable the enterprises to achieve their high-level goals.
description: Master thesis
Automatic detection of MLs targets from the bathymetry - snapshot
Creators: Vanessa Moschino
Fantina Madricardo
Valentina Grande
Antonio Petrizzo
Publisher: name: CNR-ISMAR
Year: 2022

description: A dedicated workflow in ArcGIS was developed to identify targets from the bathymetry within the MAELSTROM Project - Smart technology for MArinE Litter SusTainable RemOval and Management
Supporting Information: Effect of cement/silica ratio, aluminum hydroxide, temperature, and time on the modulus of rupture of fiber cement composites
Creators: name: Londoño Calderón, César Leandro
name: Hincapié Rojas, Daniel Fernando
name: Moscoso Londoño, Oscar
name: Escobar Rincon, Daniel
name: Pineda Goméz, Posidia
Publisher: name: figshare
Year: 2023
Subjects: Composite and hybrid materials

description: This file corresponds to the paper's supporting information: Effect of cement/silica ratio, aluminum hydroxide, temperature, and time on the modulus of rupture of fiber cement composites.
2021 International Aircraft Cabin Air Conference: Conference Proceedings
Creators: name: Global Cabin Air Quality Executive (GCAQE)
Publisher: name: Hamburg : Aircraft Design and Systems Group (AERO), Department of Automotive and Aeronautical Engineering, Hamburg University of Applied Sciences
Year: 2021
Subjects: subject: aircraft
subject: cabin
subject: cabin air
subject: ECS
subject: tricresyl phosphate
subject: TCP
subject: air
subject: contamination
subject: Konferenzschrift
subject: Luftfahrt
subject: Luftfahrzeug
subject: Flugzeugkabine
subject: Trikresylphosphat
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau::629,1 | Luft- und Raumfahrttechnik
subject: Aeronautics
subject: Airplanes
subject: Air--Pollution
subject: Aircraft Cabins

description: The International Aircraft Cabin Air Conferences have developed into a series of conferences that were organized so far in 2017, 2019 and 2021. The conferences are mapping the business, regulatory and technical solutions to aircraft cabin air contamination. These proceedings contain the contributions to the conference in 2021. From the 39 contributions to the conference 33 are included in the proceedings. Most contributions are contained in the proceedings in form of a presentation. Some are contained in more than one format (adding an extended abstract or a paper). For this reason the proceedings contain 48 documents and links to 11 short documentary films, all together on 791 pages.
Continuous Open Access Special Issue "Aircraft Design": Number 2/2020
Creators: name: (:Unkn) Unknown
Publisher: name: Basel : MDPI
Year: 2020
Subjects: subject: aerospace
subject: aviation
subject: aircraft
subject: aircraft design
subject: publishing
subject: open access
subject: special issue
subject: amphibious
subject: jet engine
subject: wing flutter
subject: optimization
subject: Blended Wing Body
subject: BWB
subject: control surface
subject: electro-impulse
subject: de-icing
subject: Flugzeugentwurf
subject: Luftfahrt
subject: Luftfahrzeug
subject: Flugzeugbau
subject: Open Access
subject: Flugtriebwerk
subject: Tragflügel
subject: Flugzeugentwurf
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau::629,1 | Luft- und Raumfahrttechnik
subject: Aeronautics
subject: Airplanes
subject: Aeronautical engineering

description: Following the successful initial Special Issue on “Aircraft Design (SI-1/2017)”, this is already the second SI “Aircraft Design (SI-2/2020)”. Activities in the past showed that aircraft design may be a field too small to justify its own (subscription-based) journal. A continuous open access special issue may fill the gap. As such, the Special Issue “Aircraft Design” can be a home for all those working in the field who regret the absence of an aircraft design journal. SI-2/2020 contains seven papers; an Editorial: 1.) "Publishing in 'Aircraft Design' with a Continuous Open Access Special Issue" and six Original Research Articles about 2.) Amphibious Aircraft Developments, 3.) Design Space Exploration of Jet Engine Components, 4.) Study of Subsonic Wing Flutter, 5.) Design Optimization of a Blended Wing Body Aircraft, 6.) Discrete Mobile Control Surfaces, 7.) Electro-Impulse De-Icing Systems.
Continuous Open Access Special Issue "Aircraft Design": Number 3/2021
Creators: name: (:Unkn) Unknown
Publisher: name: Basel : MDPI
Year: 2021
Subjects: subject: aerospace
subject: aviation
subject: aircraft
subject: aircraft design
subject: publishing
subject: open access
subject: special issue
subject: oil
subject: fumes
subject: smoke
subject: cabin
subject: flight safety
subject: flying qualities
subject: Box Wing Aircraft
subject: BWA
subject: electric propulsion
subject: fully-electric
subject: regional flight
subject: medium range
subject: optimization
subject: turboprop
subject: Kabinenluft
subject: Flugzeugentwurf
subject: Flugeigenschaften
subject: Elektroflug
subject: Turboprop
subject: Luftfahrt
subject: Luftfahrzeug
subject: Flugzeugbau
subject: Open Access
subject: Kabine
subject: Sicherheit
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau::629,1 | Luft- und Raumfahrttechnik
subject: Aeronautics
subject: Airplanes
subject: Aeronautical engineering

description: Following the successful initial Special Issue on "Aircraft Design (SI-1/2017)" and the relaunch with "Aircraft Design (SI-2/2020)", this is already the third SI in sequence named "Aircraft Design (SI 3/2021)". Activities in the past showed that aircraft design may be a field too small to justify its own (subscription-based) journal. A continuous open access special issue may fill the gap. As such, the Special Issue "Aircraft Design" can be a home for all those working in the field who regret the absence of an aircraft design journal. SI-3/2021 contains six papers (original research articles) about 1.) Oil Fumes in the Cabin and Flight Safety, 2.) Closed-Loop Flying Quality Requirements, 3.) Preliminary Design of a Medium Range Box Wing Aircraft, 4.) Influence of Novel Airframe Technologies on the Feasibility of Fully-Electric Regional Aviation, 5.) Design and Optimization of a Large Turboprop Aircraft, 6.) Sources of Onboard Fumes and Smoke.
Fundamental Tradeoff between Storage and Latency in Cache-Aided Wireless Interference Networks
Creators: name: Xu, Fan
name: Tao, Meixia
name: Liu, Kangqi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: This paper studies the fundamental tradeoff between storage and latency in a general wireless interference network with caches equipped at all transmitters and receivers. The tradeoff is characterized by an information-theoretic metric, \emph{normalized delivery time} (NDT), which is the worst-case delivery time of the actual traffic load at a transmission rate specified by degrees of freedom (DoF) of a given channel. We obtain both an achievable upper bound and a theoretical lower bound of the minimum NDT for any number of transmitters, any number of receivers, and any feasible cache size tuple. We show that the achievable NDT is exactly optimal in certain cache size regions, and is within a bounded multiplicative gap to the theoretical lower bound in other regions. In the achievability analysis, we first propose a novel cooperative transmitter/receiver coded caching strategy. It offers the freedom to adjust file splitting ratios for NDT minimization. We then propose a delivery strategy which transforms the considered interference network into a new class of cooperative X-multicast channels. It leverages local caching gain, coded multicasting gain, and transmitter cooperation gain (via interference alignment and interference neutralization) opportunistically. Finally, the achievable NDT is obtained by solving a linear programming problem. This study reveals that with caching at both transmitter and receiver sides, the network can benefit simultaneously from traffic load reduction and transmission rate enhancement, thereby effectively reducing the content delivery latency.
description: To appear in IEEE Transactions on Information Theory
title: Implementierung einer strukturunabhängigen Dynamikmodellierung für parallelkinematische Maschinen
title: Implementation of a Structurally Independant Dynamics Modelling of Parallel Kinematic Machines
titleType: AlternativeTitle
Creators: name: Job, Tim-David
Publisher: name: Hannover : Leibniz Universität Hannover, Institut für Mechatronische Systeme
Year: 2018
Subjects: subject: Parallelkinematische Maschine
subject: Dynamik
subject: Modellierung
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau

description: Das Ziel dieser Arbeit ist die Implementierung einer automatischen Dynamikmodellierung für parallelkinematische Maschinen. Diese dient unter anderem der automatischen Struktur- und Maßsynthese neuartiger Roboter in Abhängigkeit einer vorgegeben Aufgabenspezifikation. Als Grundlage wird eine bereits vorhandene Maple-Toolbox verwendet, mit der aber bisher nur serielle und hybride Strukturen berechnet werden können. Da der zu implementierende Ansatz nach Abdellatif et al. auf der getrennten Betrachtung der Beinketten und der Plattform basiert, wurde die Toolbox so erweitert, dass auf die vorhandenen Lösungen für serielle Ketten zurückgegriffen werden kann. Um das Dynamikmodell, das über den Lagrange'sche Formalismus aufgestellt wird, in Minimalform zu erhalten, werden die Bewegungsgleichungen der Teilsysteme in den Plattform-Koordinatenraum projiziert. Als Referenz dienen in dieser Arbeit zwei weitere Implementierungen zur Berechnung der Dynamik, die auf einer ähnlichen Projektion auf Basis der kinematischen Zwangsbedingungen bzw. auf der Verwendung der Newton-Euler-Methode basieren. Die Lösungen wurden hinsichtlich Recheneffizienz, Struktur der Lösung und verfahrensbedingte Begrenzungen für verschiedene Roboterstrukturen untersucht und mit denen der Referenzen verglichen.
An index obstruction to positive scalar curvature on fiber bundles over aspherical manifolds
Creators: name: Zeidler, Rudolf
Publisher: name: arXiv
Year: 2015
Subjects: subject: K-Theory and Homology (math.KT)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 58J22 (Primary) 53C23, 46L80 (Secondary)

description: We exhibit geometric situations, where higher indices of the spinor Dirac operator on a spin manifold $N$ are obstructions to positive scalar curvature on an ambient manifold $M$ that contains $N$ as a submanifold. In the main result of this note, we show that the Rosenberg index of $N$ is an obstruction to positive scalar curvature on $M$ if $N \hookrightarrow M \twoheadrightarrow B$ is a fiber bundle of spin manifolds with $B$ aspherical and $π_1(B)$ of finite asymptotic dimension. The proof is based on a new variant of the multi-partitioned manifold index theorem which might be of independent interest. Moreover, we present an analogous statement for codimension one submanifolds. We also discuss some elementary obstructions using the $\hat{A}$-genus of certain submanifolds.
description: 12 pages; v2: Changed title, minor revision following the referee's suggestions. To appear in Algebr. Geom. Topol
Influence of the laser frequency drift in phase-sensitive optical time-domain reflectometry
Creators: name: Zhirnov, A. A.
name: Stepanov, K. V.
name: Chernutsky, A. O.
name: Fedorov, A. K.
name: Nesterov, E. T.
name: Svelto, C.
name: Pnev, A. B.
name: Karasik, V. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The influence of the laser frequency drift on the operation of phase-sensitive optical time-domain reflectometry ($Φ$-OTDR) systems is considered. Theoretical results based on a new numerical $Φ$-OTDR model demonstrating the influence of the laser frequency instability on a signal are reported. This model is verified based on experimental data. It has been used to calculate the signal-to-noise ratio (SNR) of the system for different parameters of the laser source stability. As a result, quantitative requirements for lasers used in $Φ$-OTDR systems are formulated.
description: 8 pages, 7 figure
Zur aerodynamischen Berechnung eines Windenergiekonverters am Beispiel des Wagner-Rotors
Creators: name: Lindemann, Dieter
Publisher: name: Hannover : Institut für Mechanik, Universität Hannover
Year: 1985
Subjects: subject: Blade Element Momentum Theory
subject: BEMT
subject: WECS
subject: Wagner-Rotor
subject: Horizontalachsrotor
subject: Hütter
subject: Windenergie
subject: Windturbine
subject: Aerodynamik
subject: FORTRAN
subject: Windrad
subject: Differentialgeometrie
subject: Auftrieb
subject: Strömungsabriss
subject: Aerodynamisches Profil
subject: Schiff
subject: Offshore-Technik
subject: Dewey Decimal Classification::600 | Technik
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau
subject: Wind power
subject: Wind turbines
subject: Aerodynamics
subject: FORTRAN (Computer program language)
subject: Wind energy conversion systems
subject: Differential Geometry

description: Zweck - Dieser Bericht zeigt die aerodynamische Berechnung eines Windrades mit einer Geometrie, die allgemeiner definiert ist, als üblich. So ein Windrad ist auch als Wagner-Rotor bekannt und zeigt einem Achswinkel möglicherweise deutlich verschieden von 0° (Horizontalachsrotor) und einem Konuswinkel der Flügel deutlich kleiner als 90°. Der Wind strömt dabei in den, von den Flügeln gebildeten Kegel hinein. Da der Wagner-Rotor bei entsprechender Wahl dieser Winkel keinen Turm benötigt, und daher eine geringe Höhe des Schwerpunktes hat, kann er auch auf einem Schiff montiert werden und die hohen Windstärken auf See nutzen. --- Methodik - Die aerodynamischen Windradberechnung erfolgt nach Hütter (auch bekannt als Blade Element Momentum Theory, BEMT), wobei sich die Elemente hier bei dieser Berechnung über den Radius und zusätzlich über den Umfang verteilen. Die Anströmung jedes Elementes am Wagner-Rotor wird mittels Differentialgeometrie berechnet. Auftriebs- und Widerstandsbeiwerte des Flügelprofils müssen (z. B. aus Profilkatalogen) über einen großen Bereich des Anstellwinkels bekannt sein. Die Berechnung erfolgt mit einem Programm geschrieben in FORTRAN. --- Ergebnisse - Die Wirkungsgrade des Wagner-Rotors sinken, je weiter man sich von den Winkeln des Horizontalachsrotors entfernt. Es muß weiter berücksichtigt werden, daß die Windradleistung beim Wagner-Rotor nicht nur durch die schlechteren Wirkungsgrade fällt, sondern auch dadurch, daß sich bei konstanter Flügellänge die Projektionsfläche des Windrades zum Wind verkleinert. Trotzdem hat der Wagner-Rotor seine Berechtigung bei der Nutzung der Windleistung auf See, weil der Windenergiekonverter auf einem Schiff montiert werden kann. An Land können die Kosten für den Turm gegenüber dem Horizontalachsrotor reduziert werden. Ob dies die geringere Leistung bezogen auf die Flügellänge ausgleicht, kann hier nicht geklärt werden. Bedeutung für die Praxis – Dieser Ansatz ermöglicht auch eine genauere Berechnung von "Horizontalachsrotoren", die oft kleine Abweichungen der Rotorachse von der Horizontalen und Konuswinkel von etwas weniger als 90° aufweisen. Originalität / Wert – Die Aerodynamik des Wagner-Rotors wird hier erstmals in dieser Detailtiefe berechnet.
Spin Seebeck effect at microwave frequencies
Creators: name: Schreier, Michael
name: Kramer, Franz
name: Huebl, Hans
name: Geprägs, Stephan
name: Gross, Rudolf
name: Goennenwein, Sebastian T. B.
name: Noack, Timo
name: Langner, Thomas
name: Serga, Alexander A.
name: Hillebrands, Burkard
name: Vasyuchka, Vitaliy I.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We experimentally study the transient voltage response of yttrium iron garnet/platinum bilayer samples subject to periodic heating up to gigahertz frequencies. We observe an intrinsic cutoff frequency of the induced thermopower voltage, which characteristically depends on the thickness of the yttrium iron garnet film. The cutoff frequency reaches values of up to 350 MHz in a 50 nm thick yttrium iron garnet film, but drops to below 1 MHz for several-micrometer-thick films. These data corroborate the notion that the magnon spectrum responsible for the spin current emission in the spin Seebeck effect can be shaped by tuning the thickness of the ferromagnetic layer.
Common database for gender equality audit
Creators: name: Holubová, Barbora
name: Bianchi, Gabriel
name: Žilinská, Miroslava
Publisher: name: Zenodo
Year: 2022
Subjects: gender equality
database
Research performing organization (RPO)
Research funding organization (RFO)

description: This report provides data and information collected within the WP2 of the project, namely the Task 2.1 Gender equality audit and assessment at the organisational level. Under this task, the project partners carried out quantitative and qualitative gender audits in their organisations. This collection aimed to provide a solid basis for the development of gender equality plans in project partners´ organisations and fulfil the matrix with their data at the organisational level. The data and information collected will fil in a common database for Gender Equality Audit. The methodology of the gender equality audit (GEA) was prepared by the Institute for Social Communication Research of the Slovak Academy of Sciences (UVSK SAV) team in cooperation with the University of Bucharest (UB) and University Jana Kochanowskiego in Kielce (UJK) teams. Although the project consortium consists of various types of research organisations, the indicators reflect the RPO/HEI organisation’s circumstances primarily, as this type prevails among the partners. However, other types of organisation have been encouraged to collect the indicators adjusted to their conditions or indicate that the calculation of the indicators was not applicable (n/a).
Many-Body Quantum Optics with Decaying Atomic Spin States: ($γ$, $κ$) Dicke model
Creators: name: Gelhausen, Jan
name: Buchhold, Michael
name: Strack, Philipp
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We provide a theory for quantum-optical realizations of the open Dicke model with internal, atomic spin states subject to spontaneous emission with rate $γ$. This introduces a second decay channel for excitations to irreversibly dissipate into the environment, in addition to the photon loss with rate $κ$, which is composed of individual atomic decay processes and a collective atomic decay mechanism. The strength of the latter is determined by the cavity geometry. We compute the mean-field non-equilibrium steady states for spin and photon observables in the long-time limit, $t\rightarrow \infty$. Although $γ$ does not conserve the total angular momentum of the spin array, we argue that our solution is exact in the thermodynamic limit, for the number of atoms $N\rightarrow \infty$. In light of recent and upcoming experiments realizing superradiant phase transitions using internal atomic states with pinned atoms in optical lattices, our work lays the foundation for the pursuit of a new class of open quantum magnets coupled to quantum light.
description: 17 pages, 6 figures; added appendix for the derivation of a collective atomic decay mechanism in a Lindblad formalism; version as published in Physical Review A
Third Group Cohomology and Gerbes over Lie Groups
Creators: name: Mickelsson, Jouko
name: Wagner, Stefan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 22E65, 22E67 (primary), 20J06, 57T10, 81R10 (secondary)

description: The topological classification of gerbes, as principal bundles with the structure group the projective unitary group of a complex Hilbert space, over a topological space $H$ is given by the third cohomology $\text{H}^3(H, \Bbb Z)$. When $H$ is a topological group the integral cohomology is often related to a locally continuous (or in the case of a Lie group, locally smooth) third group cohomology of $H$. We shall study in more detail this relation in the case of a group extension $1\to N \to G \to H \to 1$ when the gerbe is defined by an abelian extension $1\to A \to \hat N \to N \to 1$ of $N$. In particular, when $\text{H}_s^1(N,A)$ vanishes we shall construct a transgression map $\text{H}^2_s(N, A) \to \text{H}^3_s(H, A^N)$, where $A^N$ is the subgroup of $N$-invariants in $A$ and the subscript $s$ denotes the locally smooth cohomology. Examples of this relation appear in gauge theory which are discussed in the paper.
description: in J. Geom. Phys. (2016)
Radar for tracer particles
Creators: name: Ott, Felix
name: Herminghaus, Stephan
name: Huang, Kai
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We introduce a radar system capable of tracking a $5$mm spherical target continuously in three dimensions. The $10$GHz (X-band) radar system has a transmission power of $1$W and operates in the near field of the horn antennae. By comparing the phase shift of the electromagnetic wave traveling through the free space with an IQ-Mixer, we obtain the relative movement of the target with respect to the antennae. From the azimuth and inclination angles of the receiving antennae obtained in the calibration, we reconstruct the target trajectory in a three-dimensional Cartesian system. Finally, we test the tracking algorithm with target moving in circular as well as in pendulum motions, and discuss the capability of the radar system.
description: 9 pages, 8 figures
Letter from U.S. Navy Commander to William Elliot Griffis, February 11, 1911
Creators: name: No Name Supplied
Publisher: name: No Publisher Supplied
Year: 1911

description: Informs Griffis that the requested flags are packed away in boxes, but can be arranged for inspection after an appropriation of funds determined at a Session of Congress. Confirms that the flags (in all likelihood) have symbols or designs, by Griffis' request. Includes note from requested date, May 1871.
Handling missing data in large healthcare dataset: a case study of unknown trauma outcomes
Creators: name: Mirkes, E. M.
name: Coats, T. J.
name: Levesley, J.
name: Gorban, A. N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Handling of missed data is one of the main tasks in data preprocessing especially in large public service datasets. We have analysed data from the Trauma Audit and Research Network (TARN) database, the largest trauma database in Europe. For the analysis we used 165,559 trauma cases. Among them, there are 19,289 cases (13.19\%) with unknown outcome. We have demonstrated that these outcomes are not missed `completely at random' and, hence, it is impossible just to exclude these cases from analysis despite the large amount of available data. We have developed a system of non-stationary Markov models for the handling of missed outcomes and validated these models on the data of 15,437 patients which arrived into TARN hospitals later than 24 hours but within 30 days from injury. We used these Markov models for the analysis of mortality. In particular, we corrected the observed fraction of death. Two naïve approaches give 7.20\% (available case study) or 6.36\% (if we assume that all unknown outcomes are `alive'). The corrected value is 6.78\%. Following the seminal paper of Trunkey (1983) the multimodality of mortality curves has become a much discussed idea. For the whole analysed TARN dataset the coefficient of mortality monotonically decreases in time but the stratified analysis of the mortality gives a different result: for lower severities the coefficient of mortality is a non-monotonic function of the time after injury and may have maxima at the second and third weeks. The approach developed here can be applied to various healthcare datasets which experience the problem of lost patients and missed outcomes.
description: Minor editing and additions
Computing Web-scale Topic Models using an Asynchronous Parameter Server
Creators: name: Jagerman, Rolf
name: Eickhoff, Carsten
name: de Rijke, Maarten
Publisher: name: arXiv
Year: 2016
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Information Retrieval (cs.IR)
subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Topic models such as Latent Dirichlet Allocation (LDA) have been widely used in information retrieval for tasks ranging from smoothing and feedback methods to tools for exploratory search and discovery. However, classical methods for inferring topic models do not scale up to the massive size of today's publicly available Web-scale data sets. The state-of-the-art approaches rely on custom strategies, implementations and hardware to facilitate their asynchronous, communication-intensive workloads. We present APS-LDA, which integrates state-of-the-art topic modeling with cluster computing frameworks such as Spark using a novel asynchronous parameter server. Advantages of this integration include convenient usage of existing data processing pipelines and eliminating the need for disk writes as data can be kept in memory from start to finish. Our goal is not to outperform highly customized implementations, but to propose a general high-performance topic modeling framework that can easily be used in today's data processing pipelines. We compare APS-LDA to the existing Spark LDA implementations and show that our system can, on a 480-core cluster, process up to 135 times more data and 10 times more topics without sacrificing model quality.
description: To appear in SIGIR 2017
Generalized local frame transformation theory for excited species in external fields
Creators: name: Giannakeas, P.
name: Greene, Chris H.
name: Robicheaux, F.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: A rigorous theoretical framework is developed for a generalized local frame transformation theory (GLFT). The GLFT is applicable to the following systems: to Rydberg atoms or molecules in an electric field, or to negative ions in any combination of electric and/or magnetic fields. A first test application to the photoionization spectra of Rydberg atoms in an external electric field demonstrates dramatic improvement over the first version of the local frame transformation theory developed initially by Fano and Harmin. This revised GLFT theory yields non-trivial corrections because it now includes the full on-shell Hilbert space without adopting the truncations in the original theory. Comparisons of the semi-analytical GLFT Stark spectra with {\it ab initio} numerical simulations yields errors in the range of a few tens of MHz, an improvement over the original Fano-Harmin theory whose errors are 10-100 times larger. Our analysis provides a systematic pathway to precisely describe the corresponding photoabsorption spectra that should be accurate enough to meet most modern experimental standards.
description: 9 pages, 3 figure
Quetiapine and other antipsychotic medications during pregnancy: a 15-year follow-up of a university hospital birth register
Creators: name: Kananen, Anniina
name: Bernhardsen, Guro Pauck
name: Lehto, Soili Marianne
name: Huuskonen, Pasi
name: Kokki, Hannu
name: Keski-Nisula, Leea
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: Immunology
subject: FOS: Clinical medicine
subject: Mathematical Sciences not elsewhere classified
subject: Developmental Biology
subject: Mental Health
subject: Infectious Diseases
subject: FOS: Health sciences

description: To survey trends of antipsychotic use during pregnancy and examine the associations between the use of quetiapine or any antipsychotic and adverse obstetric and neonatal outcomes. Birth register study of 36,083 women who gave birth at Kuopio University Hospital, Finland, between 2002 and 2016. Obstetric and neonatal outcomes between women using quetiapine (N = 152) or any antipsychotic (N = 227) were compared to controls (N = 35,133). Altogether 246 (0.7%) women used antipsychotic medications during pregnancy and 153 (62,2%) of these women used quetiapine. Antipsychotic usage increased from 0.4% to 1.0% during the 15-year follow-up. Women using antipsychotics were more likely to smoke, drink alcohol, use illicit drugs, use other psychotropic medications, and have higher pre-pregnancy body mass index. Quetiapine use was associated with higher risk of increased postpartum bleeding in vaginal delivery (aOR 1.65; 95%CI 1.13–2.42), prolonged neonatal hospitalization (≥5 days) (aOR 1.54; 95%CI 1.10–2.15), and higher placental to birth weight ratio (PBW ratio) (aB 0.009; 95%CI 0.002–0.016). Use of any antipsychotic was associated with a higher risk of gestational diabetes mellitus (aOR 1.64; 95%CI 1.19–2.27), increased postpartum bleeding in vaginal delivery (aOR 1.50; 95%CI 1.09–2.07), prolonged neonatal hospitalization (≥5 days) (aOR 2.07; 95%CI 1.57–2.73), and higher PBW ratio (aB 0.007; 95%CI 0.001–0.012). The use of antipsychotic medications increased among Finnish pregnant women from 2002 to 2016. Pregnant women using antipsychotics appear to have a higher risk for some adverse pregnancy and birth outcomes and may benefit from more frequent maternity care follow-ups.
Observation of Unusual Magnetoelastic Effects in a Quasi-1D Spiral Magnet
Creators: name: Wang, Chong
name: Yu, Daiwei
name: Liu, Xiaoqiang
name: Chen, Rongyan
name: Du, Xinyu
name: Hu, Biaoyan
name: Wang, Lichen
name: Iida, Kazuki
name: Kamazawa, Kazuya
name: Wakimoto, Shuichi
name: Feng, Ji
name: Wang, Nanlin
name: Li, Yuan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present a systematic study of spin and lattice dynamics in the quasi-one-dimensional spiral magnet CuBr2, using Raman scattering in conjunction with infrared and neutron spectroscopy. Along with the development of spin correlations upon cooling, we observe a rich set of broad Raman bands at energies that correspond to phonon-dispersion energies near the one-dimensional magnetic wave vector. The low-energy bands further exhibit a distinct intensity maximum at the spiral magnetic ordering temperature. We attribute these unusual observations to two possible underlying mechanisms: (1) formation of hybrid spin-lattice excitations, and/or (2) "quadrumerization" of the lattice caused by spin-singlet entanglement in competition with the spiral magnetism.
description: 4 pages, 4 figures; SM available upon request