cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Ionization of deep impurities by far-infrared radiation
Creators: name: Ganichev, Sergey
name: Yassievich, Irina
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 1997
Subjects: subject: 530 Physik

description: An analysis is made of the ionization of deep impurity centers by high-intensity far-infrared and submillimeter-wavelength radiation, with photon energies tens of times lower than the impurity ionization energy. Within a broad range of intensities and wavelengths, terahertz electric fields of the exciting radiation act as a dc field. Under these conditions, deep-center ionization can be described as multiphonon-assisted tunneling, in which carrier emission is accompanied by defect tunneling in configuration space and electron tunneling in the electric field. The field dependence of the ionization probability permits one to determine the defect tunneling times and the character of the defect adiabatic potentials. The ionization probability deviates from the field dependence e(E)}exp(E2/Ec 2) (where E is the wave field, and Ec is a characteristic field) corresponding to multiphonon-assisted tunneling ionization in relatively low fields, where the defects are ionized through the Poole–Frenkel effect, and in very strong fields, where the ionization is produced by direct tunneling without thermal activation. The effects resulting from the high radiation frequency are considered and it is shown that, at low temperatures, they become dominant.
Longtime behavior for oscillations of an extensible viscoelastic beam with elastic external supply
Creators: name: Bochicchio, Ivana
name: Vuk, Elena
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: This work is focused on a nonlinear equation describing the oscillations of an extensible viscoelastic beam with fixed ends, subject to distributed elastic external force. For a general axial load $β$, the existence of a finite/infinite set of stationary solutions and buckling occurrence are scrutinized. The exponential stability of the straight position is discussed. Finally, the related dynamical system in the history space framework is shown to possess a regular global attractor.
description: 16 pages, 2 figures
EU-Turkey Relations and Irregular Migration: Transactional Cooperation in the Making
Creators: name: Dimitriadi, Angeliki
name: Kaya, Ayhan
name: Kale, Başak
name: Zurabishvili, Tinatin
Publisher: name: Zenodo
Year: 2018
Subjects: European Union; Turkey; EU-Turkey Relations; Irregular Migration; 1999-2017; Southern Neighbourhood; Transactional Cooperation; Dynamics; Transactional; Operational; Cooperation; Migration Management

description: FEUTURE Online Paper No. 16

The aim of the paper is twofold. First, to outline the relationship of the EU and Turkey in the field of irregular migration and present the main drivers that underpin the relations from 1999 to 2017. While acknowledging that emphasis on irregular migration is given particularly post-2011, the paper argues that the dynamics characterising the relationship between Turkey and the EU do not change significantly in the pre-and post-2011 period. Secondly, the paper presents the most likely of the three scenarios- conflict, cooperation, and convergence- in the area of irregular migration drawing from the drivers of the past and present in the EU, Turkey, but also the Southern neighbourhood and beyond. The paper argues that though conflict is unlikely, equally so is convergence, with a model of transactional operational cooperation more likely and reflective of EU-Turkey relation on irregular migration management.
description: This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 692976. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Transformation elastodynamics and active exterior acoustic cloaking
Creators: name: Vasquez, Fernando Guevara
name: Milton, Graeme W.
name: Onofrei, Daniel
name: Seppecher, Pierre
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 74B05, 35J05, 74J05

description: This chapter consists of three parts. In the first part we recall the elastodynamic equations under coordinate transformations. The idea is to use coordinate transformations to manipulate waves propagating in an elastic material. Then we study the effect of transformations on a mass-spring network model. The transformed networks can be realized with "torque springs", which are introduced here and are springs with a force proportional to the displacement in a direction other than the direction of the spring terminals. Possible homogenizations of the transformed networks are presented, with potential applications to cloaking. In the second and third parts we present cloaking methods that are based on cancelling an incident field using active devices which are exterior to the cloaked region and that do not generate significant fields far away from the devices. In the second part, the exterior cloaking problem for the Laplace equation is reformulated as the problem of polynomial approximation of analytic functions. An explicit solution is given that allows to cloak larger objects at a fixed distance from the cloaking device, compared to previous explicit solutions. In the third part we consider the active exterior cloaking problem for the Helmholtz equation in 3D. Our method uses the Green's formula and an addition theorem for spherical outgoing waves to design devices that mimic the effect of the single and double layer potentials in Green's formula.
description: Submitted as a chapter for the volume "Acoustic metamaterials: Negative refraction, imaging, lensing and cloaking", Craster and Guenneau ed., Springer
Investigating the dynamics of point helical vortices on a rotating sphere to model tropical cyclones
Creators: name: Cherfanov, Sergey G.
name: Mokhov, Igor I.
name: Chefranov, Alexander G.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences

description: A general exact weak solution to the nonlinear equation of the conservation of the absolute vorticity in a thin layer of an incompressible medium on a rotating sphere is proposed. It takes into account the helicity of the point vortices and the non-uniformity of the depth of the layer. This is used to develop a model of the observed interactions of spiral atmospheric vortices. The fusion of two point helical vortices (HVs) on the rotating sphere is considered. We also analyze the prognostic applicability of the dynamics of the HVs for modeling the abrupt changes observed in the trajectories of tropical cyclones and their landfall in comparison with the traditional approach. The analytical condition for chiral symmetry violation related to the direction of the movement of the center of a helical cyclone is obtained.
description: 45 pages, 7 figures
Review: Tunnel ionization of deep impurities in semiconductors induced by terahertz electric fields
Creators: name: Ganichev, Sergey
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: Tunnel ionization; Terahertz; Far-infrared; Deep centers
subject: 530 Physik

description: An analysis is made of the ionization of deep impurity centers induced by high-intensity terahertz radiation whose photon energies are tens of times lower than the impurity ionization energy. Under these conditions, ionization can be described as phonon-assisted tunneling in which carrier emission is accompanied by defect tunneling in configuration space and electron tunneling in the electric field of the radiation. At high intensities the ionization is caused by direct tunneling. Within a broad range of intensity, frequency and temperature, the terahertz electric field of the radiation acts like a static field. For very high frequencies and low temperatures an enhancement in tunneling as compared to static fields takes place.
Pattern Formation in Semiconductors
Creators: name: Belkov, Vassilij
name: Hirschinger, J.
name: Niedernostheide, F.
name: Ganichev, Sergey
name: Prettl, Wilhelm
name: Novák, V.
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: 530 Physik

description: In semiconductors, nonlinear generation and recombination processes of free carriers and nonlinear charge transport can give rise to non-equilibrium phase transitions. At low temperatures, the basic nonlinearity is due to the autocatalytic generation of free carriers by impact ionization of shallow impurities. The electric field accelerates free electrons, causing an abrupt increase in free carrier density at a critical electric field. In static electric fields, this nonlinearity is known to yield complex filamentary current patterns bound to electric contacts.
Short-Time Critical Dynamics of Damage Spreading in the Two-Dimensional Ising Model
Creators: name: Puzzo, M. Leticia Rubio
name: Albano, Ezequiel V.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The short-time critical dynamics of propagation of damage in the Ising ferromagnet in two dimensions is studied by means of Monte Carlo simulations. Starting with equilibrium configurations at $T= \infty$ and magnetization $M=0$, an initial damage is created by flipping a small amount of spins in one of the two replicas studied. In this way, the initial damage is proportional to the initial magnetization $M_0$ in one of the configurations upon quenching the system at $T_C$, the Onsager critical temperature of the ferromagnetic-paramagnetic transition. It is found that, at short times, the damage increases with an exponent $θ_D=1.915(3)$, which is much larger than the exponent $θ=0.197$ characteristic of the initial increase of the magnetization $M(t)$. Also, an epidemic study was performed. It is found that the average distance from the origin of the epidemic ($\langle R^2(t)\rangle$) grows with an exponent $z^* \approx η\approx 1.9$, which is the same, within error bars, as the exponent $θ_D$. However, the survival probability of the epidemics reaches a plateau so that $δ=0$. On the other hand, by quenching the system to lower temperatures one observes the critical spreading of the damage at $T_{D}\simeq 0.51 T_C$, where all the measured observables exhibit power laws with exponents $θ_D = 1.026(3)$, $δ= 0.133(1)$, and $z^*=1.74(3)$.
description: 11 pages, 9 figures (included). Phys. Rev. E (2010), in press.
Active racism and the 'invisible workload' : the experiences of racialized female journalists in Canadian media
Creators: name: Zoledziowski, Anya Krystyna
Publisher: name: University of British Columbia
Year: 2019

description: Previous studies have found that female visible minority journalists experience various forms of sexism and racism in Canadian newsrooms. This thesis combines Journalism Studies and Critical Race Theory (CRT) in order to build on previous research and examine the experiences of racialized female journalists working in urban Canadian mainstream newsrooms. Through seven semi-structured interviews, five main themes emerged, many of which reiterate previous findings: (1) The racialized female reporters challenge dominant positivist norms in journalism, like objectivity; (2) These reporters have had to tailor their news stories in ways that appeal to white, usually male, editors; (3) Many of the women have experienced racism in the form of microaggressions and tokenization in newsrooms; (4) The interviewees have spent significant time educating their white colleagues on the nuances of race issues; and (5) The subjects value mentorship and “informal networks of support” in order to help other women and people of colour succeed in journalism. In contrast to previous findings, the subjects voiced an emboldened attitude towards challenging racial hierarchies in journalism spheres. Additionally, all interviewees voiced their desire to see enhanced representation of women of colour and Indigenous women in Canadian media. Particular attention is paid to how sexism and racism operate simultaneously in the lives of these reporters.
Mapped Karst Groundwater Basins in the Hopkinsville 30 X 60 Minute Quadrangle
Creators: name: Currens, James C.
name: Ray, Joseph A.
name: O'dell, Phillip W.
name: Blair, Robert J.
Publisher: name: Kentucky Geological Survey, University of Kentucky
Year: 2015

description: Copyright: © 2015, University of Kentucky, Kentucky Geological Survey
Light emission of dental enamel after multiphoton excitation
Creators: name: Lohner, Andrea
name: Huber, W.
name: Ganichev, Sergey
name: Diener, J.
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 1998
Subjects: subject: Light emission; Infrared resonant excitation; CO2 laser; Dental enamel; Hydroxyapatite; PO4 mode
subject: 530 Physik
subject: 42.65.−k
subject: 78.55.−m
subject: 87.50.Hj

description: A visible emission of dental enamel has been observed after infrared excitation by pulsed CO2 radiation well below the ablation level. The visible radiation can only be detected in narrow resonant frequency ranges of irradiation in the infrared which correspond to vibrational excitation in the stretch mode of the PO4 group. The IR induced visible luminescence of dental enamel is investigated by spectrally and temporally resolved measurements. Possible mechanisms of energy transfer are discussed.
Distinction between the Poole-Frenkel and tunneling models of electric field-stimulated carrier emission from deep levels in semiconductors
Creators: name: Ganichev, Sergey
name: Ziemann, E.
name: Yassievich, Irina
name: Prettl, Wilhelm
name: Istratov, A.
name: Weber, E.
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 530 Physik

description: The enhancement of the emission rate of charge carriers from deep-level defects in electric field is routinely used to determine the charge state of the defects. However, only a limited number of defects can be satisfactorily described by the Poole-Frenkel theory. An electric field dependence different from that expected from the Poole-Frenkel theory has been repeatedly reported in the literature, and no unambiguous identification of the charge state of the defect could be made. In this article, the electric field dependencies of emission of carriers from DX centers in AlxGa1-xAs:Te, Cu pairs in silicon, and Ge:Hg have been studied applying static and terahertz electric fields, and analyzed by using the models of Poole-Frenkel and phonon assisted tunneling. It is shown that phonon assisted tunneling and Poole-Frenkel emission are two competitive mechanisms of enhancement of emission of carriers, and their relative contribution is determined by the charge state of the defect and by the electric-field strength. At high-electric field strengths carrier emission is dominated by tunneling independently of the charge state of the impurity. For neutral impurities, where Poole-Frenkel lowering of the emission barrier does not occur, the phonon assisted tunneling model describes well the experimental data also in the low-field region. For charged impurities the transition from phonon assisted tunneling at high fields to Poole-Frenkel effect at low fields can be traced back. It is suggested that the Poole-Frenkel and tunneling models can be distinguished by plotting logarithm of the emission rate against the square root or against the square of the electric field, respectively. This analysis enables one to unambiguously determine the charge state of a deep-level defect.
title: Designing Nationality: The production of image and identity by the Argentinean State
Creators: name: Guerrini, Sebastian
Publisher: name: University of Kent
Year: 2022

description: The aim of this research is to understand how images created and spread by the Argentine State from 1810 to 2008 have contributed to the definition of national identity. This work considers that the Ideological State Apparatus creates dominant hegemonic ideologies as well as fixing certain sentiments in a given nation, producing thus its nationality. For that reason, the state uses the apparatus of cultural fictions which spreads designed symbolic fictions and images. This happens due the social importance of images and the social importance of the act of seeing, of representing, of interpreting, of imagining and of desiring as the sources that give power to images. But in order to do so, the state has to embody certain common content and to have the power to institutionalize that content. In addition, it needs a support, channels to spread nationality discourses through material culture such as public architecture, monuments, statues, the rosette, uniforms, banknotes, flag, shield and mass media. In this case, the focus of the analysis has been the flag, the shield and the banknotes. In Argentina, there have been twelve Ideological State Apparatuses which expressed, by their images and objects, different national sentiments. The organizational dimension' and the sentiments of sharing are the most common sentiments. Moreover, the proprietary and religious sentiments are more attached to the shield, while the sentiment of organization is more related to the flag. As a general conclusion, it is possible to find four identities created by the Argentine state which are the European identity, Republican identity, Nationalist identity and worker's identity. Furthermore, those identities projected four models of exclusive identities due to the symbolic absence of differences in their produced images, such as diversity of genre, physiognomies, ethnics, provinces and the lack of inclusion of some very popular democratic figures.
Near-zone field effect of FIR laser radiation on tunnel current through the Schottky barrier under plasma reflection condition
Creators: name: Shul'man, A.
name: Ganichev, Sergey
name: Kotel'nikov, I.
name: Dizhur, E.
name: Prettl, Wilhelm
name: Ormont, A.
name: Fedorov, Y.
name: Zepezauer, E.
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: 530 Physik

description: Far infrared (FIR) radiation of high-power pulsed laser incident normal to the surface of GaAs/metal tunnel structures with a self-consistent Schottky barrier gives rise to a change in the tunnel conductance. It has been shown that the observed photoresistive effects are caused by ponderomotive forces of the radiation field on the free electron plasma in the junctions. The change of tunnel conductance rises linearly with increasing intensity at low power levels and proceeds into a strongly superlinear dependence at high intensities. It is shown that this superlinearity is a result of an enhancement of the local radiation field in the near zone of diffraction by inhomogeneities at the metal-semiconductor interface and depends strongly on the roughness of the metal electrode. Experimental results are compared to a nonlinear extension of the theory of electron redistribution due to the radiation pressure.
On geometrical interpretation of alignment phenomenon
Creators: name: Lokhtin, I. P.
name: Nikolskii, A. V.
name: Snigirev, A. M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The observed alignment of spots in the x-ray films in cosmic ray emulsion experiments is analyzed and interpreted in the framework of geometrical approach. It is shown that the high degree of alignment can appear partly due to the selection procedure of most energetic particles itself and the threshold on the energy deposition together with the transverse momentum conservation.
description: 8 pages, 5 figures, the additional investigations done for the different types of region symmetry. Version accepted for publication in Eur. Phys. J. C
Buckling and longterm dynamics of a nonlinear model for the extensible beam
Creators: name: Bochicchio, Ivana
name: Vuk, Elena
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: This work is focused on the longtime behavior of a non linear evolution problem describing the vibrations of an extensible elastic homogeneous beam resting on a viscoelastic foundation with stiffness k>0 and positive damping constant. Buckling of solutions occurs as the axial load exceeds the first critical value, β_c, which turns out to increase piecewise-linearly with k. Under hinged boundary conditions and for a general axial load P, the existence of a global attractor, along with its characterization, is proved by exploiting a previous result on the extensible viscoelastic beam. As P
description: 14 pages, 2 figures
Spin-dependent terahertz nonlinearities at inter-valence-band absorption in p-Ge
Creators: name: Ganichev, Sergey
name: Ketterl, Hermann
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: Far-infrared; Multi-photon absorption; Saturation; Spin
subject: 530 Physik

description: Far-infrared absorption and photon drag effect have been investigated in p-type germanium as a function of intensity of a high-power pulsed far-infrared molecular laser. Optical transmission shows saturation independent of the state of polarization of the radiation whereas in the photon drag effect a pronounced linear–circular dichroism occurs. Linear–circular dichroism is caused by spin-selective excitations as a result of selection rules and, equally important, multi-photon transitions with a rate comparable to one-photon absorption.
title: Understanding sex disparities in tuberculosis and assessing the potential impact of strategies to improve men’s access to care
Creators: name: Horton, KS
Publisher: name: London School of Hygiene & Tropical Medicine
Year: 2021

description: Background: Tuberculosis (TB) case notifications among men outnumber those among women, yet sex disparities in TB burden and access to care are not well-understood. Methods: Systematic reviews, meta-analyses, and mathematical modelling were utilised to estimate sex disparities in TB burden and access to care, to identify drivers of those disparities in Viet Nam and Malawi, to explore sex-specific factors underlying those drivers, and to quantify the potential epidemiological impact of sex-specific strategies to further improve access to care in Viet Nam. Results: The prevalence of bacteriologically positive TB was twice as high in men as in women in low- and middle-income countries, and gaps in detection and reporting were 50% higher among men. Sex disparities in Viet Nam and Malawi were attributable to higher TB incidence and untreated disease duration in men, the latter being a year longer than in women. Sex-assortative mixing patterns that emerge in adulthood likely contribute to men’s higher incidence. Future interventions to improve access to diagnosis and treatment were projected to be most effective at reducing the epidemiological burden of TB in men, women, and children when rates of access to TB care improved in both men and women as a result of those interventions. Conclusion: Men have a higher epidemiological burden of TB and less access to care than women due to a complex nexus of biological and socio-cultural factors. Global strategies and national TB programmes should recognise men as a key affected population and prioritise men’s access to care in order to reduce TB morbidity and mortality in men, women, and children.
Characterization of deep impurities in semiconductors by terahertz tunneling ionization
Creators: name: Ziemann, E.
name: Ganichev, Sergey
name: Yassievich, Irina
name: Perel, V.
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 530 Physik

description: Tunneling ionization in high frequency fields as well as in static fields is suggested as a method for the characterization of deep impurities in semiconductors. It is shown that an analysis of the field and temperature dependences of the ionization probability allows to obtain defect parameters like the charge of the impurity, tunneling times, the Huang–Rhys parameter, the difference between optical and thermal binding energy, and the basic structure of the defect adiabatic potentials. Compared to static fields, high frequency electric fields in the terahertz-range offer various advantages, as they can be applied contactlessly and homogeneously even to bulk samples using the intense radiation of a high power pulsed far-infrared laser. Furthermore, impurity ionization with terahertz radiation can be detected as photoconductive signal with a very high sensitivity in a wide range of electric field strengths.
Terahertz tunnel ionization of DX centers in AlGaAs:Te
Creators: name: Ketterl, Hermann
name: Ziemann, E.
name: Ganichev, Sergey
name: Belyaev, A.
name: Schmult, Stefan
name: Prettl, Wilhelm
name: Yassievich, Irina
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: DX-center; Persistent photoconductivity; Ionization; Tunneling
subject: 530 Physik

description: Ionization of DX-centers in AlGaAs : Te has been investigated in strong terahertz electric fields of FIR-laser radiation with photon energies much smaller than the impurity binding energy. Detachment of electrons from DX-centers is caused by phonon-assisted tunneling being independent of the field frequency as long as the tunneling time is smaller than the field period. In the opposite case an enhancement of the emission probability with rising frequency has been observed. At very high-field strengths direct tunneling without involving phonons dominates and finally emission rates get frequency independent.
A Short Survey of Cyclic Cohomology
Creators: name: Khalkhali, Masoud
Publisher: name: arXiv
Year: 2010
Subjects: subject: Operator Algebras (math.OA)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 58B34 (Primary), 19D55 (Secondary), 16T05, 18G30

description: This is a short survey of some aspects of Alain Connes' contributions to cyclic cohomology theory in the course of his work on noncommutative geometry over the past 30 years.
description: To appear in: CMI Proceedings of Noncommutative Geometry Conference in honor of ALAIN CONNES' 60th birthday
Calibration of Muon Reconstruction Algorithms Using an External Muon Tracking System at the Sudbury Neutrino Observatory
Creators: name: SNO Collaboration
Publisher: name: arXiv
Year: 2011
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: To help constrain the algorithms used in reconstructing high-energy muon events incident on the Sudbury Neutrino Observatory (SNO), a muon tracking system was installed. The system consisted of four planes of wire chambers, which were triggered by scintillator panels. The system was integrated with SNO's main data acquisition system and took data for a total of 95 live days. Using cosmic-ray events reconstructed in both the wire chambers and in SNO's water Cherenkov detector, the external muon tracking system was able to constrain the uncertainty on the muon direction to better than 0.6 degrees.
description: 8 pages, 11 figures. Submitted to NIM A
EU and Turkish Energy Interests in the Caspian and Middle East Region
Creators: name: Ala'Aldeen, Dlawer
name: Palani, Kamaran
name: Babunashvili, Giorgi
name: Balisdell, Jackson
Publisher: name: Zenodo
Year: 2018
Subjects: European Union; Turkey; EU-Turkey Relations; Energy Interests; Caspian Region; Middle East Region; Energy-Sector Drivers; ME&CB; Energy Driver; Oil; Gas; Eastern Supply; Western Demand; Geopolitics; Iran

description: FEUTURE Online Paper No. 13

 This paper aims to identify energy-sector drivers at the regional level in the Middle East and Caspian Basin (ME&CB), examine their impact on EU–Turkey relations and classify them based on whether they are likely to result in conflict, cooperation and/or convergence. We found that multiple energy drivers strategically incentivize the EU and Turkey to cooperate and converge on overall political and economic policies and priorities. As European consumers (and many others) seek greater energy security and the ME&CB is poised to supply the EU and Turkey with the lion’s share of their oil and gas needs, Turkey is ideally situated to bridge between Eastern supply and Western demand. This symbiotic relationship provides additional incentives for cooperation and/or convergence in the short, medium and long term. However, Turkey and the EU must first shift from conflict to cooperation and/or convergence on larger geopolitical issues regarding migration, counterterrorism, the war in Syria, Turkey’s enhanced relations with Russia and Iran, and Turkey’s domestic politics. Otherwise, the two sides will fail to realize the full range of mutual benefits.
description: This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 692976. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Leveraging driver vehicle and environment interaction: Machine learning using driver monitoring cameras to detect drunk driving
Creators: name: Koch, Kevin
name: Maritsch, Martin
name: van Weenen, Eva
name: Feuerriegel, Stefan
name: Pfäffli, Matthias
name: Fleisch, Elgar
name: Weinmann, Wolfgang
name: Wortmann, Felix
Publisher: name: arXiv
Year: 2023
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Excessive alcohol consumption causes disability and death. Digital interventions are promising means to promote behavioral change and thus prevent alcohol-related harm, especially in critical moments such as driving. This requires real-time information on a person's blood alcohol concentration (BAC). Here, we develop an in-vehicle machine learning system to predict critical BAC levels. Our system leverages driver monitoring cameras mandated in numerous countries worldwide. We evaluate our system with n=30 participants in an interventional simulator study. Our system reliably detects driving under any alcohol influence (area under the receiver operating characteristic curve [AUROC] 0.88) and driving above the WHO recommended limit of 0.05g/dL BAC (AUROC 0.79). Model inspection reveals reliance on pathophysiological effects associated with alcohol consumption. To our knowledge, we are the first to rigorously evaluate the use of driver monitoring cameras for detecting drunk driving. Our results highlight the potential of driver monitoring cameras and enable next-generation drunk driver interaction preventing alcohol-related harm.
Fast room temperature detection of state of circular polarization of terahertz radiation
Creators: name: Ganichev, Sergey
name: Ketterl, H.
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 2003
Subjects: subject: circular photogalvanic effect; fast infrared detection; helicity of radiation
subject: 530 Physik

description: We report on a room temperature detector which allows to determine and monitor the state of polarization of terahertz radiation with picosecond temporal resolution. The detector is based on the circular photogalvanic effect recently observed in GaAs/AlGaAs quantum wells. The circular photogalvanic effect yields in response to elliptically polarized radiation a current signal proportional to the degree of circular polarization. The peak current signal occurs in unbiased samples for circular polarization, vanishes at linear polarization and changes sign by switching the helicity from right-handed to left-handed. The detector consists of a (113)A MBE grown pGaAs/AlGaAs multiple quantum well structure. The response has been measured in the wavelength range between 76 m and 280 m at normal incidence of the radiation on the sample.
Global and exponential attractors for a Ginzburg-Landau model of superfluidity
Creators: name: Berti, Alessia
name: Berti, Valeria
name: Bochicchio, Ivana
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The long-time behavior of the solutions for a non-isothermal model in superfluidity is investigated. The model describes the transition between the normal and the superfluid phase in liquid 4He by means of a non-linear differential system, where the concentration of the superfluid phase satisfies a non-isothermal Ginzburg-Landau equation. This system, which turns out to be consistent with thermodynamical principles and whose well-posedness has been recently proved, has been shown to admit a Lyapunov functional. This allows to prove existence of the global attractor which consists of the unstable manifold of the stationary solutions. Finally, by exploiting recent techniques of semigroups theory, we prove the existence of an exponential attractor of finite fractal dimension which contains the global attractor.
description: 39 pages
Gossiped and Quantized Online Multi-Kernel Learning
Creators: name: Ortega, Tomas
name: Jafarkhani, Hamid
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics
subject: G.1.6; F.2.1; E.4
subject: 68W10, 68W15, 68W40, 90C06, 90C25, 90C35

description: In instances of online kernel learning where little prior information is available and centralized learning is unfeasible, past research has shown that distributed and online multi-kernel learning provides sub-linear regret as long as every pair of nodes in the network can communicate (i.e., the communications network is a complete graph). In addition, to manage the communication load, which is often a performance bottleneck, communications between nodes can be quantized. This letter expands on these results to non-fully connected graphs, which is often the case in wireless sensor networks. To address this challenge, we propose a gossip algorithm and provide a proof that it achieves sub-linear regret. Experiments with real datasets confirm our findings.
Руська дружина на Балканах
Creators: name: Орлов, Руслан
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 430101
subject: Archaeological science

description: Орлов Р.С. Руська дружина на Балканах // Проблеми походження та історичного розвитку слов'ян.- Київ-Львів, 1997. - С.194-208
Nano metal fluorides: small particles with great properties
Creators: name: Kemnitz, Erhard
name: Mahn, Stefan
name: Krahl, Thoralf
Publisher: name: Humboldt-Universität zu Berlin
Year: 2020
Subjects: subject: Non-aqueous fluorolytic sol–gel synthesis
subject: Nanoscopic metal fluorides
subject: Mechanism
subject: Applications
subject: 540 Chemie und zugeordnete Wissenschaften

description: The recently developed fluorolytic sol–gel route to metal fluorides opens a very broad range of both scientific and technical applications of the accessible high surface area metal fluorides, many of which have already been applied or tested. Specific chemical properties such as high Lewis acidity and physical properties such as high surface area, mesoporosity and nanosize as well as the possibility to apply metal fluorides on surfaces via a non-aqueous sol make the fluorolytic synthesis route a very versatile one. The scope of its scientific and technical use and the state of the art are presented.
Accurate evaluation of self-heterodyne laser linewidth measurements using Wiener filters
Creators: name: Kantner, Markus
name: Mertenskötter, Lutz
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Self-heterodyne beat note measurements are widely used for the experimental characterization of the frequency noise power spectral density (FN-PSD) and the spectral linewidth of lasers. The measured data, however, must be corrected for the transfer function of the experimental setup in a post-processing routine. The standard approach disregards the detector noise and thereby induces reconstruction artifacts, i.e., spurious spikes, in the reconstructed FN-PSD. We introduce an improved post-processing routine based on a parametric Wiener filter that is free from reconstruction artifacts, provided a good estimate of the signal-to-noise ratio is supplied. Building on this potentially exact reconstruction, we develop a new method for intrinsic laser linewidth estimation that is aimed at deliberate suppression of unphysical reconstruction artifacts. Our method yields excellent results even in the presence of strong detector noise, where the intrinsic linewidth plateau is not even visible using the standard method. The approach is demonstrated for simulated time series from a stochastic laser model including 1/f-type noise.
Slave-spin mean field for broken-symmetry states: Néel antiferromagnetism and its phase separation in multi-orbital Hubbard models
Creators: name: Crispino, Matteo
name: Chatzieleftheriou, Maria
name: Gorni, Tommaso
name: Medici, Luca de'
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We introduce the generalization of the Slave-Spin Mean-Field method to broken-symmetry phases. Through a variational approach we derive the single-particle energy shift in the mean-field equations which generates the appropriate self-consistent field responsible for the stabilization of the broken symmetry. With this correction the different flavours of the slave-spin mean-field are actually the same method and they give identical results to Kotliar-Ruckenstein slave-bosons and to the Gutzwiller approximation. We apply our formalism to the Néel antiferromagnetic state and study it in multi-orbital models as a function of the number of orbitals and Hund's coupling strength, providing phase diagrams in the interaction-doping plane. We show that the doped antiferromagnet in proximity of half-filling is typically unstable towards insulator-metal and magnetic-non magnetic phase separation. Hund's coupling extends the range of this antiferromagnet, and favors its phase separation.
description: 15 pages, 10 figures
Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations II: Resolution Effects
Creators: name: Christensen, Charlotte
name: Quinn, Thomas
name: Stinson, Gregory
name: Bellovary, Jillian
name: Wadsley, James
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We examine the effect of mass and force resolution on a specific star formation (SF) recipe using a set of N-body/Smooth Particle Hydrodynamic simulations of isolated galaxies. Our simulations span halo masses from 10^9 to 10^13 solar masses, more than four orders of magnitude in mass resolution, and two orders of magnitude in the gravitational softening length, epsilon, representing the force resolution. We examine the total global star formation rate, the star formation history, and the quantity of stellar feedback and compare the disk structure of the galaxies. Based on our analysis, we recommend using at least 10^4 particles each for the dark matter and gas component and a force resolution of epsilon approximately equal to 10^-3 R_vir when studying global SF and feedback. When the spatial distribution of stars is important, the number of gas and dark matter particles must be increased to at least 10^5 of each. Low mass resolution simulations with fixed softening lengths show particularly weak stellar disks due to two-body heating. While decreasing spatial resolution in low mass resolution simulations limits two-body effects, density and potential gradients cannot be sustained. Regardless of the softening, low-mass resolution simulations contain fewer high density regions where SF may occur. Galaxies of approximately 10^10 solar masses display unique sensitivity to both mass and force resolution. This mass of galaxy has a shallow potential and is on the verge of forming a disk. The combination of these factors give this galaxy the potential for strong gas outflows driven by supernova feedback and make it particularly sensitive to any changes to the simulation parameters.
description: 34 pages, 7 figures. Accepted for publication in ApJ.
31861: Working with wildlife
Creators: name: Project, Lockdown2020 and Beyond
Publisher: name: University of Oxford
Year: 2023
Subjects: classificationCode: 479999
subject: Other language, communication and culture not elsewhere classified

description: Working on the table in the front window, being distracted by passing dog walkers, shoppers, exercisers and the birds on the feeder. A pile of Beano annuals to put my laptop on for meetings so my camera is at a better angle. I used to feel embarrassed about being on camera but we're all in the same boat. And I like seeing others (and their decor, pets, ... yes, I'm nosey :) Husband is taking a break from working to go Zwifting on the patio, watched by the fox that has moved in next door. One teenager still asleep upstairs but will be studying at midnight. The other a lark, doing schoolwork then gaming with friends. Feeling grateful we have space, greenery, children who don't need much attention, that we all get on well, and also, in a way that feels a bit odd, that my parents died years ago so I don't have to worry about them being old and living so far away.
Western hemlock regeneration on coarse woody debris is facilitated by linkage into a mycorrhizal network in an old-growth forest
Creators: name: Orrego, Gabriel
Publisher: name: University of British Columbia
Year: 2018

description: Western hemlock (Tsuga heterophylla (Raf.) Sarg.) is the climax tree species in most of the low elevation Pacific northwest coastal forests. Regeneration of western hemlock under a closed canopy it is tightly associated with coarse woody debris (CWD). Nurse-logs contain physical, chemical and biological features that make them the most suitable seedbed for hemlock in old-growth forests. However, the preference of western hemlock for CWD is still not completely understood. Few studies have investigated belowground dynamics related to western hemlock growing on decayed wood, specifically ectomycorrhizal (EM) associations and the potential access to a mycorrhizal network (MN). My research addressed two objectives: 1) To compare establishment and survival of western hemlock germinants among different microsites (CWD with different wood breakdown levels and forest floor) in the forest understory; and 2) To investigate whether carbon is transferred through mycorrhizal networks from mature trees to seedlings established on CWD. To accomplish this, I pulse-labeled ¹³C-glucose solution into the phloem of mature trees. I found that western hemlock successful recruitment was associated with the presence of medium to advanced decay classes of CWD. I also found the first evidence that there is carbon transfer from mature trees to regenerating seedlings established on CWD. I conclude that western hemlock regeneration on nurse-logs is facilitated by mycorrhizal networks of canopy trees in an old-growth forest of coastal British Columbia.
Critical exponents of domain walls in the two-dimensional Potts model
Creators: name: Dubail, Jérôme
name: Jacobsen, Jesper Lykke
name: Saleur, Hubert
Publisher: name: arXiv
Year: 2010
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We address the geometrical critical behavior of the two-dimensional Q-state Potts model in terms of the spin clusters (i.e., connected domains where the spin takes a constant value). These clusters are different from the usual Fortuin-Kasteleyn clusters, and are separated by domain walls that can cross and branch. We develop a transfer matrix technique enabling the formulation and numerical study of spin clusters even when Q is not an integer. We further identify geometrically the crossing events which give rise to conformal correlation functions. This leads to an infinite series of fundamental critical exponents h_{l_1-l_2,2 l_1}, valid for 0 - Q - 4, that describe the insertion of l_1 thin and l_2 thick domain walls.
description: 5 pages, 3 figures, 1 table
Simplifying the axiomatization for the ordered affine geometry via a theorem prover
Creators: name: Li, Dafa
Publisher: name: arXiv
Year: 2023
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics

description: Based on an ordering with directed lines and using constructions instead of existential axioms, von Plato proposed a constructive axiomatization of the ordered affine geometry. There are 22 axioms for the ordered affine geometry, of which the axiom I.7 is about the convergence of three lines (ignoring their directions). In this paper, we indicate that the axiom I.7 includes much redundancy, and demonstrate that the complicated axiom I.7 can be replaced equivalently with a simpler and more intuitive new axiom via a theorem prover.
description: 23 pages, no figure. arXiv admin note: text overlap with arXiv:2205.05162
TAUVEX: status in 2011
Creators: name: Brosch, Noah
name: Murthy, Jayant
Publisher: name: arXiv
Year: 2011
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present a short history of the TAUVEX instrument, conceived to provide multi-band wide-field imaging in the ultraviolet, emphasizing the lack of sufficient and aggressive support on the part of the different space agencies that dealt with this basic science mission. First conceived in 1985 and selected by the Israel Space Agency in 1989 as its first priority payload, TAUVEX is fast becoming one of the longest-living space project of space astronomy. After being denied a launch on a national Israeli satellite, and then not flying on the Spectrum X-Gamma (SRG) international observatory, it was manifested since 2003 as part of ISRO's GSAT-4 Indian satellite to be launched in the late 2000s. However, two months before the launch, in February 2010, it was dismounted from its agreed-upon platform. This proved to be beneficial, since GSAT-4 and its launcher were lost on April 15 2010 due to the failure of the carrier rocket's 3rd stage. TAUVEX is now stored in ISRO's clean room in Bangalore with no firm indications when or on what platform it might be launched.
description: Invited contribution presented at the "UV Universe 2010". Accepted for publication in Astrophysics & Space Science
Conversion of spin into directed electric current in quantum wells
Creators: name: Ganichev, Sergey
name: Danilov, Sergey
name: Eroms, Jonathan
name: Wegscheider, Werner
name: Weiss, Dieter
name: Prettl, Wilhelm
name: Ivchenko, Eougenious
Publisher: name: Universität Regensburg
Year: 2001
Subjects: subject: 530 Physik

description: A nonequilibrium population of spin-up and spin-down states in quantum well structures has been achieved applying circularly polarized radiation. The spin polarization results in a directed motion of free carriers in the plane of a quantum well perpendicular to the direction of light propagation. Because of the spin selection rules the direction of the current is determined by the helicity of the light and can be reversed by switching the helicity from right to left handed. A microscopic model is presented which describes the origin of the photon helicity driven current. The model suggests that the system behaves as a battery which generates a spin polarized current.