cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Soft phonons and structural phase transition in superconducting Ba0.59K0.41BiO3
Creators: name: Kang, H. J.
name: Lee, Y. S.
name: Lynn, J. W.
name: Shiryaev, S. V.
name: Barilo, S. N.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We have observed a softening of phonons and a structural phase transition in a superconducting Ba0.59K0.41BiO3 (Tc = 31 K) single crystal using elastic and inelastic neutron scattering measurements. The soft phonon occurs for the [111] transverse acoustic mode at the zone boundary. The phonon energies in this vicinity are found to continuously decrease with decreasing temperature from above room temperature to 200 K, where a structural phase transition from cubic to tetragonal symmetry occurs. The overall results are consistent with previous data that reported phonon softening and a (0.5, 0.5, 0.5) type superstructure in several Ba1-xKxBiO3 systems. However, we also find weak (0.5, 0.5, 0) type superstructure peaks that reveal an additional component to the modulation. No significant change related to the superconductivity was observed for the soft phonon energies or linewidths.
description: 15 pages
Fitting Bell Curves to Data Distributions using Visualization
Creators: name: Newburger, Eric
name: Correll, Michael
name: Elmqvist, Niklas
Publisher: name: arXiv
Year: 2023
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Idealized probability distributions, such as normal or other curves, lie at the root of confirmatory statistical tests. But how well do people understand these idealized curves? In practical terms, does the human visual system allow us to match sample data distributions with hypothesized population distributions from which those samples might have been drawn? And how do different visualization techniques impact this capability? This paper shares the results of a crowdsourced experiment that tested the ability of respondents to fit normal curves to four different data distribution visualizations: bar histograms, dotplot histograms, strip plots, and boxplots. We find that the crowd can estimate the center (mean) of a distribution with some success and little bias. We also find that people generally overestimate the standard deviation, which we dub the "umbrella effect" because people tend to want to cover the whole distribution using the curve, as if sheltering it from the heavens above, and that strip plots yield the best accuracy.
Higher-order Kerr terms allow ionization-free filamentation in gases
Creators: name: Béjot, P.
name: Kasparian, J.
name: Henin, S.
name: Loriot, V.
name: Vieillard, T.
name: Hertz, E.
name: Faucher, O.
name: Lavorel, B.
name: Wolf, J. -P.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We show that higher-order nonlinear indices ($n_4$, $n_6$, $n_8$, $n_{10}$) provide the main defocusing contribution to self-channeling of ultrashort laser pulses in air and Argon at 800 nm, in contrast with the previously accepted mechanism of filamentation where plasma was considered as the dominant defocusing process. Their consideration allows to reproduce experimentally observed intensities and plasma densities in self-guided filaments.
description: 11 pages, 6 figures (11 panels)
A Facile Strategy to a New Fluorous-Tagged, Immobilized TEMPO Catalyst Using a Click Reaction, and Its Catalytic Activity
Creators: name: Gheorghe, Alexandru
name: Cuevas-Yañez, Erick
name: Horn, Joachim
name: Bannwarth, Willi
name: Narsaiah, Banda
name: Reiser, Oliver
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: catalyst immobilization; fluorous; oxidation; click chemistry; TEMPO
subject: 540 Chemie

description: A new fluorous-tagged TEMPO catalyst was prepared by a facile approach using the copper-catalyzed azide-alkyne cycloaddition as the ligation method. A fluorous F17-CLICK-TEMPO showed excellent activity and selectivity in the oxidation of alcohols to aldehydes using bleach as the terminal oxidant. Moreover, the catalyst could be easily recovered using silica gel 60 and recycled in four cycles without loss of activity.
Ficha técnica, índice e Nota prévia
Creators: name: Vasconcelos, Paulo
Publisher: name: Revista de Ciências Empresariais e Jurídicas / Review of Business and Legal Sciences
Year: 2021

description: Revista de Ciências Empresariais e Jurídicas / Review of Business and Legal Sciences, N.º 31 (2021): Revista de Ciências Empresariais e Jurídicas / Review of Business and Legal Sciences
Generation of far-infrared pulses by use of a passively mode-locked high-pressure CO_{2} laser
Creators: name: Lang, P.
name: Schatz, W.
name: Renk, Karl Friedrich
name: Beregulin, E.
name: Ganichev, Sergey
name: Yaroshetskii, I.
Publisher: name: Universität Regensburg
Year: 1990
Subjects: subject: 530 Physik

description: Our present study demonstrates for the first time generation of frequency-tunable intense infrared radiation pulses in the nanosecond time regime by mode-locking a high pressure CO2 laser using p-doped germanium as a saturable absorber. These pulses were transferred into the FIR region via stimulated Raman scattering of the CO2 laser radiation in CH3F resulting in subnanosecond FIR laser pulses
Tevatron Higgs Mass Bounds: Projecting U(1)' Models to LHC Domain
Creators: name: Sert, Hale
name: Cincioglu, Elif
name: Demir, Durmus A.
name: Solmaz, Levent
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study Higgs boson masses in supersymmetric models with an extra U(1) symmetry to be called U(1)$^{\prime}$. Such extra gauge symmetries are urged by the $μ$ problem of the MSSM, and they also arise frequently in low-energy supersymmetric models stemming from GUTs and strings. We analyze mass of the lightest Higgs boson and various other particle masses and couplings by taking into account the LEP bounds as well as the recent bounds from Tevatron experiments. We find that the $μ$-problem motivated generic low-energy U(1)$^{\prime}$ model yields Higgs masses as large as $\sim 200\ {\rm GeV}$ and violate the Tevatron bounds for certain ranges of parameters. We analyze correlations among various model parameters, and determine excluded regions by both scanning the parameter space and by examining certain likely parameter values. We also make educated projections for LHC measurements in light of the Tevatron restrictions on the parameter space. We further analyze certain benchmark models stemming from E(6) breaking, and find that they elevate Higgs boson mass into Tevatron's forbidden band when U(1)$^{\prime}$ gauge coupling takes larger values than the one corresponding to one-step GUT breaking.
description: 11 pages, 3 figures
Modular synthesis of chiral pentadentate bis(oxazoline) ligands
Creators: name: Seitz, Michael
name: Kaiser, Anja
name: Tereshchenko, Alexander
name: Geiger, Christian
name: Uematsu, Yukitaka
name: Reiser, Oliver
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: 540 Chemie

description: Highly modular N,Y,Z,Y,N-ligands (Y=N, O, S; Z=N, NO, OH, OMe) have been prepared using bis(oxazoline) building blocks either as nucleophiles or as electrophiles in coupling reactions with central aromatic units. This way, a great variety of pentadentate bis(oxazoline) ligands in diastereo- and enantiomerically pure form become readily available, which are useful for the construction of helical metal complexes with predetermined chirality.
Observation of magneto-phonon resonance of Dirac fermions in graphite
Creators: name: Yan, J.
name: Goler, S.
name: Rhone, T. D.
name: Han, M.
name: He, R.
name: Kim, P.
name: Pellegrini, V.
name: Pinczuk, A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Coherent coupling of Dirac fermion magneto-excitons with an optical phonon is observed in graphite as marked magnetic-field dependent splittings and anti-crossing behavior of the two coupled modes. The sharp magneto-phonon resonance occurs in regions of the graphite sample with properties of superior single-layer graphene having enhanced lifetimes of Dirac fermions. The greatly reduced carrier broadening to values below the graphene electron-phonon coupling constant explains the appearance of sharp resonances that reveal a fundamental interaction of Dirac fermions.
description: 5 figures, supplementary material section included
title: Anytime algorithms for ROBDD symmetry detection and approximation
Creators: name: Kettle, Neil
Publisher: name: University of Kent
Year: 2022

description: Reduced Ordered Binary Decision Diagrams (ROBDDs) provide a dense and memory efficient representation of Boolean functions. When ROBDDs are applied in logic synthesis, the problem arises of detecting both classical and generalised symmetries. State-of-the-art in symmetry detection is represented by Mishchenko's algorithm. Mishchenko showed how to detect symmetries in ROBDDs without the need for checking equivalence of all co-factor pairs. This work resulted in a practical algorithm for detecting all classical symmetries in an ROBDD in O(|G|³) set operations where |G| is the number of nodes in the ROBDD. Mishchenko and his colleagues subsequently extended the algorithm to find generalised symmetries. The extended algorithm retains the same asymptotic complexity for each type of generalised symmetry. Both the classical and generalised symmetry detection algorithms are monolithic in the sense that they only return a meaningful answer when they are left to run to completion. In this thesis we present efficient anytime algorithms for detecting both classical and generalised symmetries, that output pairs of symmetric variables until a prescribed time bound is exceeded. These anytime algorithms are complete in that given sufficient time they are guaranteed to find all symmetric pairs. Theoretically these algorithms reside in O(n³+n|G|+|G|³) and O(n³+n²|G|+|G|³) respectively, where n is the number of variables, so that in practice the advantage of anytime generality is not gained at the expense of efficiency. In fact, the anytime approach requires only very modest data structure support and offers unique opportunities for optimisation so the resulting algorithms are very efficient. The thesis continues by considering another class of anytime algorithms for ROBDDs that is motivated by the dearth of work on approximating ROBDDs. The need for approximation arises because many ROBDD operations result in an ROBDD whose size is quadratic in the size of the inputs. Furthermore, if ROBDDs are used in abstract interpretation, the running time of the analysis is related not only to the complexity of the individual ROBDD operations but also the number of operations applied. The number of operations is, in turn, constrained by the number of times a Boolean function can be weakened before stability is achieved. This thesis proposes a widening that can be used to both constrain the size of an ROBDD and also ensure that the number of times that it is weakened is bounded by some given constant. The widening can be used to either systematically approximate an ROBDD from above (i.e. derive a weaker function) or below (i.e. infer a stronger function). The thesis also considers how randomised techniques may be deployed to improve the speed of computing an approximation by avoiding potentially expensive ROBDD manipulation.
title: Keeping Arctic fisheries as happy as a clam: assessing the life history and density of truncated soft-shell clams (Mya truncata) of southern Baffin Island, Nunavut, to promote sustainable fishery development
Creators: name: Wood, Jessica Marie
Publisher: name: Memorial University of Newfoundland
Year: 2020

description: Fishery development is a priority for Arctic governments, Indigenous organizations, and communities to promote Arctic economic development and food security. The recreational truncated soft-shell clam (Mya truncata) fishery of southern Baffin Island, Nunavut, is expected to undergo increased fishing pressure with northern population expansion and potential commercial development in Frobisher Bay and on the north shore of the Hudson Strait. Understanding aspects of the life history and population density of M. truncata of southern Baffin Island is key to sustainable fishery development. I first found the shell length at 50% sexual maturity to be 31 and 32mm in male and female M. truncata, respectively. Based on the stage of gonadal development observed in sexually mature clams collected from inner Frobisher Bay in late August 2018 and Hudson Strait in early September 2018, I suspect a late-summer or fall spawning event may have taken place in 2018. I identified strong length-bias in calculated condition indices for these populations, and so I used dry-body weight to shell length relationships to gauge population condition over small and large spatial scales. I then implemented a drop-camera set-up using the frame of a snow crab trap, a GoPro, lasers and a weight strung on a monofilament line for scale to assess M. truncata density in the intertidal zone. By comparing drop-camera density estimates with those obtained by manual excavations, I determined that drop-camera deployments within the intertidal zone estimate significantly less clams than excavation estimates across all sites. This difference was attributed to smaller clam siphons not being visible in video, the retraction of siphons at low tide, and fine sediment displacement with tidal flow covering siphons. This research is expected to help with community-based resource harvest plans and conservation measures and to inform policy at regional, territorial, and national levels.
Carrier tunneling in high-frequency electric fields
Creators: name: Ganichev, Sergey
name: Ziemann, E.
name: Gleim, T.
name: Prettl, Wilhelm
name: Yassievich, Irina
name: Perel, V.
name: Wilke, I.
name: Haller, E.
Publisher: name: Universität Regensburg
Year: 1998
Subjects: subject: 530 Physik
subject: 71.55.-i
subject: 72.20.Ht
subject: 72.40.+w

description: An enhancement of tunnel ionization of deep impurities in semiconductors in an alternating field as compared to static fields has been observed. The transition between the quasistatic and the high-frequency regime is determined by the tunneling time. For the case of deep impurities this is the time of redistribution of the defect vibrational system which depends strongly on temperature and the impurity structure. A theory of tunnel ionization of deep impurities by high-frequency fields has been developed.
Effect of electron heating and radiation pressure on tunneling across Schottky barrier due to giant near field of FIR radiation
Creators: name: Shul'man, A.
name: Ganichev, Sergey
name: Dizhur, E.
name: Kotel'nikov, I.
name: Zepezauer, E.
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: Tunneling; Schottky-barrier junctions; Near-"eld enhancement; Hot electrons and LO phonons in GaAs
subject: 530 Physik

description: The conductance of tunnel junctions formed by n-GaAs and a semitransparent metal electrode on its surface was shown to be changed by normally incident radiation with frequency below the plasma edge of n-GaAs. A spatial redistribution of the electrons due to the radiation pressure and the corresponding change in the shape of the self-consistent Schottky barrier are observed as a photoconductivity response. The comparison of the measured intensity dependence of the response to the theory has revealed an effective enhancement of the radiation field close to the n-GaAs/Me interface. The ratio Ke of the effective radiation intensity to the incident plain-wave intensity has turned out to be as large as 105. The high local electric field results in strong heating of the degenerate electron gas in the Schottky-barrier region that is mostly apparent as a photo-e.m.f. An analysis of the intensity dependence of the photo-e.m.f. is carried out involving the modification of the Schottky barrier by the ponderomotive force, the electron gas heating in Γ- and L-valleys, as well as the heating of LO phonons. The results confirm the value of Ke and allow to estimate the hot-electron temperature in Γ- and L-valleys.
Applications of path integral localization to gauge and string theories
Creators: name: Gordon, James B.
Publisher: name: University of British Columbia
Year: 2018

description: In the first part of this thesis we exploit supersymmetric localization to study aspects of supersymmetric gauge theories relevant to holography. In chapter 2 we study the 1/2-BPS circular Wilson loop in the totally antisymmetric representation of the gauge group in N = 4 supersymmetric Yang-Mills. We compute the first 1/N correction at leading order in ’t Hooft coupling by means of the matrix model loop equations for comparison with the 1-loop effective action of the holographically dual D5-brane. Our result suggests the need to account for gravitational backreaction on the string theory side. In chapter 3 we solve the planar N = 2* super-Yang-Mills theory at large ’t Hooft coupling again using localization on S⁴. The solution permits detailed investigation of the resonance phenomena responsible for quantum phase transitions in infinite volume, and leads to quantitative predictions for the semiclassical string dual of the N = 2* theory. The second part of the thesis deals with the Schwinger effect in scalar quantum electrodynamics and in bosonic string theory. Chapter 4 presents a detailed study of the semiclassical expansion of the world line path integral for a charged relativistic particle in a constant external electric field. It is demonstrated that the Schwinger formula for charged particle pair production is reproduced exactly by the semiclassical expansion around classical instanton solutions when the leading order of fluctuations is taken into account. By a localization argument we prove that all corrections to this leading approximation vanish and that the WKB approximation to the world line path integral is exact. Finally, in chapter 5 we analyse the problem of charged string pair creation in a constant external electric field. We find the instantons in the worldsheet sigma model which are responsible for the tunneling events, and evaluate the sigma model partition function in the multi-instanton sector in the WKB approximation. We further identify a fermionic symmetry associated with collective coordinates, which we use to localize the worldsheet functional integral onto its WKB limit, proving that our result is exact.
Dynamical Signatures of Liouvillian Flat Band
Creators: name: Liu, Yu-Guo
name: Chen, Shu
Publisher: name: arXiv
Year: 2023
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Although flat-band structures have attracted intensive studies in condensed matter and optical physics due to their eigenstates exhibiting huge degeneracy and allowing for the localization of wave packet, it is not clear how the flat band of Liouvillian influences the relaxation dynamics of open quantum systems. To this end, we study the dynamical signatures of Liouvillian flat band in the scheme of Lindblad master equation. Considering a chain model with gain and loss, we demonstrate three kinds of band dispersion of Liouvillian: flat bland, dispersionless only in the real part and imaginary part, and capture their dynamical signatures: when the rapidity spectrum of Liouvillian is flat, the particle numbers in different sites relax to its steady state value with the same decay rate; when the real or imaginary part of rapidity spectrum is dispersionless, the relaxation behaviors have oscillating or forked characteristics. We also unveil that the Liouvillian flat band can lead to dynamical localization, which is characterized by the halt of propagation of a local perturbation on the steady state.
description: 13 pages, 8 figures
Near-Solar-Circle Method for Determination of the Galactic Constants
Creators: name: Sofue, Y.
name: Nagayama, T.
name: Matsui, M.
name: Nakagawa, A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We propose a method to determine the galactic constants R_0 (distance to the Galactic Center) and V_0 (rotation velocity of the Sun) from measurements of distances, radial velocities and proper motions of objects near the solar circle. This is a modification of the solar-circle method to a more practical observational method. We apply the method to determine R_0 using data from the literature with known distances and radial velocities, and obtain R_0 = 7.54 +/- 0.77 kpc.
description: 5 pages, 4 figures, accepted for PASJ (Vol. 63 No. 5)
Visible light emission due to resonant CO_{2} excitation of dental hard tissue
Creators: name: Lohner, Andrea
name: Huber, Michael
name: Ganichev, Sergey
name: Prettl, Wilhelm
name: Niederdellmann, Herbert
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 530 Physik

description: Visible light emission of dental hard substances excited by high-power infrared pulses of a tunable TEA CO2 laser has been investigated. A clear correlation between observed visible light emission, plasma formation as well as ablation of dental hard tissue has been demonstrated. Both, the highly nonlinear infrared to visible upconversion process and the ablation efficiency show a sharp spectral resonance close to a vibrational mode of PO4 at 1090 cm-1 in dental enamel and dentin. The influence of strong infrared light impulses on dental hard tissue is examined by performing upconversion studies of visible light emission of human dental enamel and dentin. Our experimental setup allows one to determine the plasma formation threshold being important in dental surgery.
36M Dissemination/Communication Report
Creators: name: Glaskova-Kuzmina, Tatjana
Publisher: name: Zenodo
Year: 2020
Subjects: 36M progress report

description: 36M Dissemination/Communication Report for the project “Environmental effects on physical properties of smart composites and FRP modified by carbonaceous nanofillers for structural applications” (project No. 1.1.1.2/VIAA/1/16/066, Activity 1.1.1.2 “Post-doctoral Research Aid” of the Specific Aid Objective 1.1.1 “To increase the research and innovative capacity of scientific institutions of Latvia and the ability to attract external financing, investing in human resources and infrastructure” of the Operational Programme “Growth and Employment”.
GRB 090417B and its Host Galaxy: A Step Towards an Understanding of Optically-Dark Gamma-Ray Bursts
Creators: name: Holland, Stephen T.
name: Sbarufatti, Boris
name: Shen, Rongfeng
name: Schady, Patricia
name: Cummings, Jay R.
name: Fonseca, Emmanuel
name: Fynbo, Johan P. U.
name: Jakobsson, Pall
name: Leitet, Elisabet
name: Linne, Staffan
name: Roming, Peter W. A.
name: Still, Martin
name: Zhang, Bing
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: GRB 090417B was an unusually long burst with a T_90 duration of at least 2130 s and a multi-peaked light curve at energies of 15-150 keV. It was optically dark and has been associated with a bright star-forming galaxy at a redshift of 0.345 that is broadly similar to the Milky Way. This is one of the few cases where a host galaxy has been clearly identified for a dark gamma-ray burst and thus an ideal candidate for studying the origin of dark bursts. We find that the dark nature of GRB 090417B cannot be explained by high redshift, incomplete observations, or unusual physics in the production of the afterglow. Assuming the standard relativistic fireball model for the afterglow we find that the optical flux is at least 2.5 mag fainter than predicted by the X-ray flux. The Swift/XRT X -ray data are consistent with the afterglow being obscured by a dense, localized sheet of dust approximately 30-80 pc from the burst along the line of sight. Our results suggest that this dust sheet imparts an extinction of A_V >~ 12 mag, which is sufficient to explain the missing optical flux. GRB 090417B is an example of a gamma-ray burst that is dark due to the localized dust structure in its host galaxy.
description: Accepted for publication in ApJ
Magnetic field effect on tunnel ionization of deep impurities by far-infrared radiation
Creators: name: Moskalenko, A. S.
name: Ganichev, Sergey
name: Perel, V. I.
name: Yassievich, Irina
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: Magnetic field; Far infrared; Ionization rate; Deep centers
subject: 530 Physik

description: The probability of electron tunneling from a bound to a free state in an alternating electric and a constant magnetic field is calculated in the quasiclassical approximation. It is shown that the magnetic field reduces the probability of electron tunneling. The application of the external magnetic field perpendicular to the electric field reduces the ionization probability at high magnetic fields, when cyclotron resonance frequency becomes larger than reciprocal tunneling time. The increase of electric field frequency to values larger than the same reciprocal tunneling time enhances the influence of magnetic field.
Spectroscopy Study on NV Sensors in Diamond-based High-pressure Devices
Creators: name: Ho, Kin On
name: Leung, Man Yin
name: Wang, Wenyan
name: Xie, Jianyu
name: Yip, King Yau
name: Wu, Jiahao
name: Goh, Swee K.
name: Denisenko, Andrej
name: Wrachtrup, Jörg
name: Yang, Sen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Recently, the negatively charged nitrogen-vacancy (NV) center has emerged as a robust and versatile quantum sensor in pressurized environments. There are two popular ways to implement NV sensing in a diamond anvil cell (DAC), which is a conventional workhorse in the high-pressure community: create implanted NV centers (INVs) at the diamond anvil tip or immerse NV-enriched nano-diamonds (NDs) in the pressure medium. Nonetheless, there are limited studies on comparing the local stress environments experienced by these sensor types as well as their performances as pressure gauges. In this work, by probing the NV energy levels with the optically detected magnetic resonance (ODMR) method, we experimentally reveal a dramatic difference in the partially reconstructed stress tensors of INVs and NDs incorporated in the same DAC. Our measurement results agree with computational simulations, concluding that INVs perceive a more non-hydrostatic environment dominated by a uniaxial stress along the DAC axis. This provides insights on the suitable choice of NV sensors for specific purposes and the stress distribution in a DAC. We further propose some possible methods, such as using NDs and nanopillars, to extend the maximum working pressure of quantum sensing based on ODMR spectroscopy, since the maximum working pressure could be restricted by non-hydrostaticity of the pressure environment. Moreover, we explore more sensing applications of the NV center by studying how pressure modifies different aspects of the NV system. We perform a photoluminescence study using both INVs and NDs to determine the pressure dependence of the zero-phonon line, which helps developing an all-optical pressure sensing protocol with the NV center. We also characterize the spin-lattice relaxation ($T_1$) time of INVs under pressure to lay a foundation for robust pulsed measurements with NV centers in pressurized environments.
Near-field induced FIR Josephson-detection by x-axis-oriented YBa_{2}Cu_{3}O_{7-d} -films
Creators: name: Zepezauer, E.
name: Kalbeck, A.
name: Ganichev, Sergey
name: Korzenietz, W.
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 530 Physik

description: A novel approach to intrinsic Josephson-detection of far infrared radiation is reported utilizing near-zone field effects at electric contacts on c-axis oriented YBa2Cu3O7- films. While only a bolometric signal was observed focusing the radiation far off the contacts on c-axis normal films, irradiating the edge of contacts yielded an almost wavelength independent fast signal showing the characteristic intensity dependence of Josephson-detection. The signal is attributed to a c-axis parallel component of the electric radiation field being generated in the near-zone field of diffraction at the metallic contact structures.
title: Applying cognitive electrophysiology to neural modelling of the attentional blink
Creators: name: Craston, Patrick
Publisher: name: University of Kent
Year: 2022

description: This thesis proposes a connection between computational modelling of cognition and cognitive electrophysiology. We extend a previously published neural network model of working memory and temporal attention (Simultaneous Type Serial Token (ST2 ) model ; Bowman & Wyble, 2007) that was designed to simulate human behaviour during the attentional blink, an experimental nding that seems to illustrate the temporal limits of conscious perception in humans. Due to its neural architecture, we can utilise the ST2 model's functionality to produce so-called virtual event-related potentials (virtual ERPs) by averaging over activation proles of nodes in the network. Unlike predictions from textual models, the virtual ERPs from the ST2 model allow us to construe formal predictions concerning the EEG signal and associated cognitive processes in the human brain. The virtual ERPs are used to make predictions and propose explanations for the results of two experimental studies during which we recorded the EEG signal from the scalp of human participants. Using various analysis techniques, we investigate how target items are processed by the brain depending on whether they are presented individually or during the attentional blink. Particular emphasis is on the P3 component, which is commonly regarded as an EEG correlate of encoding items into working memory and thus seems to re ect conscious perception. Our ndings are interpreted to validate the ST2 model and competing theories of the attentional blink. Virtual ERPs also allow us to make predictions for future experiments. Hence, we show how virtual ERPs from the ST2 model provide a powerful tool for both experimental design and the validation of cognitive models.
qBounce: First Measurement of the Neutron Electric Charge with a Ramsey-type GRS Experiment
Creators: name: Bosina, Joachim
name: Filter, Hanno
name: Micko, Jakob
name: Jenke, Tobias
name: Pitschmann, Mario
name: Roccia, Stéphanie
name: Sedmik, R. I. P.
name: Abele, Hartmut
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The qBounce collaboration built over the last years a new Ramsey-type Gravitational Resonance Spectroscopy (GRS) experiment. After commissioning between 2016 and 2018, the setup was able to measure the Ramsey transitions with GRS for the first time. Here we present a search of the hypothetical charge of the neutron as an application of GRS to study nonstandard model interactions. This article will describe the measuring principle and the setup in detail.
description: Proceedings available at https://doi.org/10.58027/1e1n-7973
Wind and wave disturbance rejection control of floating offshore wind turbines
Creators: name: Cortes Sanchez, Cristopher Jesus
Publisher: name: University of British Columbia
Year: 2020

description: The past few decades have seen an increasing interest toward wind energy since it has the potential to become the main global power source in the near future. Particularly, researchers are looking towards the development of offshore wind turbines since they have the potential to be way more efficient and have a higher rated power in response to stronger and steadier offshore winds. However, the harsh marine environment places challenges on the path to making offshore wind turbines an economically viable source of energy. Specifically, wind and wave disturbances act on the wind turbines inducing harmful loads on their major components, shortening their useful life and increasing maintenance cost. In this thesis, we propose a control method that rejects both wind and wave disturbances, thus reducing fatigue loads on the wind turbine structure while also maximizing power regulation. Based on a simplified control-oriented modeling technique, both wind and wave disturbance matrices are obtained from linearized state-space systems, and used to design a disturbance rejection H∞ controller. Furthermore, the proposed control method demonstrates the usefulness of including the wave disturbance matrix in the control design process, something that has been attempted in the past but not achieved yet in offshore wind turbine research. Finally, the performance of the designed H∞ controller is validated and compared against a baseline controller using Fatigue, Aerodynamics, Structures, and Turbulence (FAST), an open-source software package capable of modeling wind turbine systems and simulating their physical dynamics with high accuracy. This comparison demonstrates the effectiveness of the proposed method.
A numerical projection technique for large-scale eigenvalue problems
Creators: name: Gamillscheg, Ralf
name: Haase, Gundolf
name: von der Linden, Wolfgang
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We present a new numerical technique to solve large-scale eigenvalue problems. It is based on the projection technique, used in strongly correlated quantum many-body systems, where first an effective approximate model of smaller complexity is constructed by projecting out high energy degrees of freedom and in turn solving the resulting model by some standard eigenvalue solver. Here we introduce a generalization of this idea, where both steps are performed numerically and which in contrast to the standard projection technique converges in principle to the exact eigenvalues. This approach is not just applicable to eigenvalue problems encountered in many-body systems but also in other areas of research that result in large scale eigenvalue problems for matrices which have, roughly speaking, mostly a pronounced dominant diagonal part. We will present detailed studies of the approach guided by two many-body models.
description: 7 pages, 4 figures
Special core tensors of multi-qubit states and the concurrency of three lines
Creators: name: Choong, Pak Shen
name: Zainuddin, Hishamuddin
name: Chan, Kar Tim
name: Husain, Sharifah Kartini Said
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Classification of multipartite states aims to obtain a set of operationally useful and finite entanglement classes under the action of either local unitary (LU) or stochastic local operation and classical communication (SLOCC). In this work, we propose a computationally simple approach to find these classes by using higher order singular value decomposition (HOSVD) and the concurrency of three lines. Since HOSVD simultaneously diagonalizes the one-body reduced density matrices (RDM) of multipartite states, the core tensor of multipartite states is the pure-state representation of such simultaneously diagonalized one-body RDM. We identified the special core tensors of three and four qubits, which are also genuinely entangled by default. The special core tensors are further categorized into families of states based on their first $n$-mode singular values, $σ_1^{(i)2}$. The current proposal is limited to multi-qubit system, but it scales well with large multi-qubit systems and produces a finite number of families of states.
description: This preprint has not undergone peer review (when applicable) or any post-submission improvements or corrections. The Version of Record of this article is published in Quantum Information Processing, and is available online at https://doi.org/10.1007/s11128-023-03939-w
Two-hadron correlations in the Color Glass Condensate formalism
Creators: name: Jalilian-Marian, Jamal
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Two-hadron correlations are a sensitive probe of the dynamics of gluon saturation and the Color Glass Condensate formalism where the degrees of freedom are Wilson lines of the gluon field. It is shown that unlike structure functions in DIS and single hadron production in proton-nucleus collisions, higher point functions of Wilson lines appear in two-hadron production cross section. We derive equations for the energy ($x$) evolution of these higher point functions using the JIMWLK Hamiltonian and show that dipole approximation, employed in the literature to fit the di-hadron data measured by the STAR collaboration in the forward rapidity region, breaks down. This necessitates an investigation of the full hierarchy of the JIMWLK evolution equations for these higher point functions and their solutions. This can then be used to make a quantitative analysis of the di-hadron correlations in the forward rapidity region in deuteron-gold collisions at RHIC and in the long range rapidity correlations observed in proton-proton collisions at the LHC.
description: 10 pages, based on talks given by the author in in the program "High Energy Strong Interactions 2010" at the Yukawa Institute for Theoretical Physics, July-August 2010, Kyoto, Japan and in the "5th International Workshop on high $p_t$ Physics at LHC 2010", September - October, 2010, Mexico City, Mexico
Slave Orchestras, Choirs, Bands, and Ensembles, A Bibliography
Creators: name: Silpayamanant, Jon
Publisher: name: figshare
Year: 2022
Subjects: subject: History
subject: 190409 Musicology and Ethnomusicology
subject: FOS: Arts (arts, history of arts, performing arts, music)
subject: 190407 Music Performance

description: This is a pdf version of the bibliography on slave ensembles first posted at Mae Mai on 8 March 2021.
Link to online version in References below.
Microwave induced patterns in n-GaAs and their photoluminescence imaging
Creators: name: Belkov, Vassilij
name: Hirschinger, J.
name: Schowalter, Dieter
name: Niedernostheide, F.-J.
name: Ganichev, Sergey
name: Prettl, Wilhelm
name: Mathúna, D.
name: Novák, V.
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 530 Physik

description: Using the technique of photoluminescence imaging, self-organized patterns of high-electron density in homogeneous n-GaAs layers under homogeneous microwave irradiation are studied. The structures are shown to be analogous to current filaments in a static electric field. The symmetry of the microwave induced patterns is not constrained by the current feeding electrodes. It is, however, concluded that a feedback mechanism exists between the formation of high-conducting structures and the homogeneity of the incident microwave irradiation.
Non-phononic density of states of two-dimensional glasses revealed by random pinning
Creators: name: Shiraishi, Kumpei
name: Mizuno, Hideyuki
name: Ikeda, Atsushi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The vibrational density of states of glasses is considerably different from that of crystals. In particular, there exist spatially localized vibrational modes in glasses. The density of states of these non-phononic modes has been observed to follow $g(ω) \propto ω^4$, where $ω$ is the frequency. However, in two-dimensional systems, the abundance of phonons makes it difficult to accurately determine this non-phononic density of states because they are strongly coupled to non-phononic modes and yield strong system-size and preparation-protocol dependencies. In this article, we utilize the random pinning method to suppress phonons and disentangle their coupling with non-phononic modes and successfully calculate their density of states as $g(ω) \propto ω^4$. We also study their localization properties and confirm that low-frequency non-phononic modes in pinned systems are truly localized without far-field contributions. We finally discuss the excess density of states over the Debye value that results from the hybridization of phonons and non-phononic modes.
description: 6 pages, 3 figures
Study of Ni-doping Effect of Specific Heat and Transport Properties for LaFe1-yNiyAsO0.89F0.11
Creators: name: Kawamata, Takayuki
name: Satomi, Erika
name: Kobayashi, Yoshiaki
name: Itoh, Masayuki
name: Sato, Masatoshi
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Specific heats and transport quantities of the LaFe1-yNiyAsO0.89F0.11 system have been measured, and the results are discussed together with those reported previously by our group mainly for LaFe1-yCoyAsO0.89F0.11 and LaFeAsO0.89-xF0.11+x systems. The y dependence of the electronic specific heat coefficient gamma can basically be understood by using the rigid-band picture, where Ni ions provide 2 electrons to the host conduction bands and behave as nonmagnetic impurities. The superconducting transition temperature Tc of LaFe1-yNiyAsO0.89F0.11 becomes zero, as the carrier density p (=2y+0.11) doped to LaFeAsO reaches its critical value p_c_ ~0.2. This p_c_ value of ~0.2 is commonly observed for LaFe1-yCoyAsO0.89F0.11 and LaFeAsO0.89-xF0.11+x systems, in which the relations p = x+0.11 and p = y+0.11 hold, respectively. As we pointed out previously, the critical value corresponds to the disappearance of the hole-Fermi surface. These results indicate that the carrier number solely determines the Tc value. We have not observed appreciable effects of pair breaking, which originates from the nonmagnetic impurity scattering of conduction electrons and strongly suppresses T_c_ values of systems with sign-reversing of the order parameter over the Fermi surface(s). On the basis of the results, the so-called s_+-_ symmetry of the order parameter with the sign-reversing is excluded.
description: 4 pages, 7 figures, submitted to J. Phys. Soc. Jpn, (modified version)
Simplistic Collection and Labeling Practices Limit the Utility of Benchmark Datasets for Twitter Bot Detection
Creators: name: Hays, Chris
name: Schutzman, Zachary
name: Raghavan, Manish
name: Walk, Erin
name: Zimmer, Philipp
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences

description: Accurate bot detection is necessary for the safety and integrity of online platforms. It is also crucial for research on the influence of bots in elections, the spread of misinformation, and financial market manipulation. Platforms deploy infrastructure to flag or remove automated accounts, but their tools and data are not publicly available. Thus, the public must rely on third-party bot detection. These tools employ machine learning and often achieve near perfect performance for classification on existing datasets, suggesting bot detection is accurate, reliable and fit for use in downstream applications. We provide evidence that this is not the case and show that high performance is attributable to limitations in dataset collection and labeling rather than sophistication of the tools. Specifically, we show that simple decision rules -- shallow decision trees trained on a small number of features -- achieve near-state-of-the-art performance on most available datasets and that bot detection datasets, even when combined together, do not generalize well to out-of-sample datasets. Our findings reveal that predictions are highly dependent on each dataset's collection and labeling procedures rather than fundamental differences between bots and humans. These results have important implications for both transparency in sampling and labeling procedures and potential biases in research using existing bot detection tools for pre-processing.
description: 10 pages, 6 figures; updated citation, clarified language
Inferring the rate of technosignatures from 60 yr of nondetection
Creators: name: Grimaldi, Claudio
Publisher: name: arXiv
Year: 2023
Subjects: subject: Popular Physics (physics.pop-ph)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: For about the last 60 years the search for extraterrestrial intelligence has been monitoring the sky for evidence of remotely detectable technological life beyond Earth, with no positive results to date. While the lack of detection can be attributed to the highly incomplete sampling of the search space, technological emissions may be actually rare enough that we are living in a time when none cross the Earth. Here we explore the latter possibility and derive the likelihood of the Earth not being crossed by signals for at least the last 60 years to infer upper bounds on their rate of emission. Under the assumption that technological emitters are distributed uniformly in the Milky Way and that they generate technoemissions at a constant rate, we find less than about one to five emissions generated per century with 95% credible level. This implies optimistic waiting times until the next crossing event of no less than 60-1800 years with a 50% probability. A significant fraction of highly directional signals increases the emission rates upper bounds, but without systematically changing the waiting time. Although these probabilistic bounds are derived from a specific model and their validity depends on the model's assumptions, they are nevertheless quite robust against weak time dependences of the emission rate or nonuniform spatial distributions of the emitters. Our results provide therefore a benchmark for assessing the lack of detection and may serve as a basis to form optimal strategies for the search for extraterrestrial intelligence.
description: 9 pages, 4 figures
General Electric Quarterly Survey 65-03, Version I & II
Creators: name: Electric, General
Publisher: name: Roper Center for Public Opinion Research
Year: 2022

description: Most important problem (1); topics of interest (3); importance of various topics (8); groups associated with various topics (2); spending additions money (1); opinions of various items (4); institutions affecting community (3); community changes (2); higher taxes for various services (12); most important company (1); company public responsibility (6); company ratings (34); knowledge about General Electric (2); changes in lifestyle (5); magazine readership (1); television viewership (16); reading habits (1); World's Fair attendance (2).